Terminal apparatus, base station apparatus, and communication method

ABSTRACT

A terminal apparatus receives a PDCCH and receive a PDSCH scheduled by the PDCCH, and transmits (reports), via a PUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH. Based at least on the PDCCH, a PDSCH group ID and a toggle bit corresponding to the PDSCH group ID are indicated. In a case that the toggle bit is toggled, HARQ-ACK information being already reported (the HARQ-ACK information other than HARQ-ACK information not being reported yet) is deleted from an HARQ-ACK codebook corresponding to the PDSCH group ID. The HARQ-ACK information corresponding to the PDSCH scheduled by the PDCCH is included in the HARQ-ACK codebook.

TECHNICAL FIELD

The present invention relates to a terminal apparatus, a base stationapparatus, and a communication method.

This application claims priority to JP 2019-111115 filed on Jun. 14,2019, the contents of which are incorporated herein by reference.

BACKGROUND ART

In the 3^(rd) Generation Partnership Project (3GPP), a radio accessmethod and a radio network for cellular mobile communications(hereinafter referred to as “Long Term Evolution (LTE)” or “EvolvedUniversal Terrestrial Radio Access (EUTRA)”) have been studied. In LTE,a base station apparatus is also referred to as an evolved NodeB(eNodeB), and a terminal apparatus is also referred to as User Equipment(UE). LTE is a cellular communication system in which multiple areascovered by a base station apparatus are distributed in a cell structure.A single base station apparatus may manage multiple serving cells.

3GPP has been studying a next generation standard (New Radio or NR)(NPL 1) to make a proposal for International Mobile Telecommunication(IMT)-2020, a standard for a next generation mobile communication systemdeveloped by the International Telecommunication Union (ITU). NR isrequired to satisfy requirements for three scenarios including enhancedMobile BroadBand (eMBB), massive Machine Type Communication (mMTC), andUltra Reliable and Low Latency Communication (URLLC) in a singletechnology framework.

CITATION LIST Non Patent Literature

NPL 1: “New SID proposal: Study on New Radio Access Technology”,RP-160671, NTT docomo, 3GPP TSG RAN Meeting #71, Goteborg, Sweden,7-10Mar., 2016.

SUMMARY OF INVENTION Technical Problem

One aspect of the present invention provides a terminal apparatus thatefficiently performs communication, a communication method used for theterminal apparatus, a base station apparatus that efficiently performscommunication, and a communication method used for the base stationapparatus.

Solution to Problem

(1) A first aspect of the present invention is a terminal apparatusincluding: a receiver configured to receive a PDCCH and receive a PDSCHscheduled by the PDCCH; and a transmitter configured to transmit(report), via a PUCCH or a PUSCH, HARQ-ACK information corresponding tothe PDSCH, wherein PDCCH #C, PDCCH #G, and PDCCH #I are received, PDSCH#C is scheduled by the PDCCH #C, PDSCH #G is scheduled by the PDCCH #G,and PDSCH #I is scheduled by the PDCCH #I, the PDCCH #G indicates asecond value, and the PDCCH #I indicates a third value, the PDCCH #Iindicates transmission of at least HARQ-ACK information #I correspondingto the PDSCH #I on PUCCH #3, in a case that the second value and thethird value are different from each other, HARQ-ACK information #Gcorresponding to the PDSCH #G and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, in a case that the second value is equal tothe third value, HARQ-ACK information #C corresponding to the PDSCH #C,the HARQ-ACK information #G, and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, the HARQ-ACK information #G is newtransmission on the PUCCH #3, and the HARQ-ACK information #C isretransmission on the PUCCH #3.

(2) A second aspect of the present invention is a terminal apparatusincluding: a receiver configured to receive a PDCCH and receive a PDSCHscheduled by the PDCCH; and a transmitter configured to transmit(report), via a PUCCH or a PUSCH, HARQ-ACK information corresponding tothe PDSCH, wherein based at least on the PDCCH, a PDSCH group ID and atoggle bit corresponding to the PDSCH group ID are indicated, in a casethat the toggle bit is toggled, HARQ-ACK information being alreadyreported (the HARQ-ACK information other than HARQ-ACK information notbeing reported yet) is deleted from an HARQ-ACK codebook correspondingto the PDSCH group ID, and the HARQ-ACK information corresponding to thePDSCH scheduled by the PDCCH is included in the HARQ-ACK codebook.

(3) A third aspect of the present invention is a base station apparatusincluding: a transmitter configured to transmit a PDCCH and transmit aPDSCH scheduled by the PDCCH; and a receiver configured to receive, viaa PUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH,wherein PDCCH #C, PDCCH #G, and PDCCH #I are transmitted, PDSCH #C isscheduled by the PDCCH #C, PDSCH #G is scheduled by the PDCCH #G, andPDSCH #I is scheduled by the PDCCH #I, the PDCCH #G indicates a secondvalue, and the PDCCH #I indicates a third value, the PDCCH #I indicatestransmission of at least HARQ-ACK information #I corresponding to thePDSCH #I on PUCCH #3, in a case that the second value and the thirdvalue are different from each other, HARQ-ACK information #Gcorresponding to the PDSCH #G and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, in a case that the second value is equal tothe third value, HARQ-ACK information #C corresponding to the PDSCH #C,the HARQ-ACK information #G, and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, the HARQ-ACK information #G is newtransmission on the PUCCH #3, and the HARQ-ACK information #C isretransmission on the PUCCH #3.

(4) A fourth aspect of the present invention is a base station apparatusincluding: a transmitter configured to transmit a PDCCH and transmit aPDSCH scheduled by the PDCCH; and a receiver configured to receive, viaa PUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH,wherein based at least on the PDCCH, a PDSCH group ID and a toggle bitcorresponding to the PDSCH group ID are indicated, in a case that thetoggle bit is toggled, HARQ-ACK information being already reported (theHARQ-ACK information other than HARQ-ACK information not being reportedyet) is deleted from an HARQ-ACK codebook corresponding to the PDSCHgroup ID, and the HARQ-ACK information corresponding to the PDSCHscheduled by the PDCCH is included in the HARQ-ACK codebook.

(5) A fifth aspect of the present invention is a communication methodused for a terminal apparatus, the communication method including thesteps of: receiving a PDCCH and receiving a PDSCH scheduled by thePDCCH; and transmitting (reporting), via a PUCCH or a PUSCH, HARQ-ACKinformation corresponding to the PDSCH, wherein PDCCH #C, PDCCH #G, andPDCCH #I are received, PDSCH #C is scheduled by the PDCCH #C, PDSCH #Gis scheduled by the PDCCH #G, and PDSCH #I is scheduled by the PDCCH #I,the PDCCH #G indicates a second value, and the PDCCH #I indicates athird value, the PDCCH #I indicates transmission of at least HARQ-ACKinformation #I corresponding to the PDSCH #I on PUCCH #3, in a case thatthe second value and the third value are different from each other,HARQ-ACK information #G corresponding to the PDSCH #G and the HARQ-ACKinformation #I are multiplexed on the PUCCH #3, in a case that thesecond value is equal to the third value, HARQ-ACK information #Ccorresponding to the PDSCH #C, the HARQ-ACK information #G, and theHARQ-ACK information #I are multiplexed on the PUCCH #3, the HARQ-ACKinformation #G is new transmission on the PUCCH #3, and the HARQ-ACKinformation #C is retransmission on the PUCCH #3.

(6) A sixth aspect of the present invention is a communication methodused for a terminal apparatus, the communication method including thesteps of: receiving a PDCCH and receiving a PDSCH scheduled by thePDCCH; and transmitting (reporting), via a PUCCH or a PUSCH, HARQ-ACKinformation corresponding to the PDSCH, wherein based at least on thePDCCH, a PDSCH group ID and a toggle bit corresponding to the PDSCHgroup ID are indicated, in a case that the toggle bit is toggled,HARQ-ACK information being already reported (the HARQ-ACK informationother than HARQ-ACK information not being reported yet) is deleted froman HARQ-ACK codebook corresponding to the PDSCH group ID, and theHARQ-ACK information corresponding to the PDSCH scheduled by the PDCCHis included in the HARQ-ACK codebook.

(7) A seventh aspect of the present invention is a communication methodused for a base station apparatus, the communication method includingthe steps of: transmitting a PDCCH and transmitting a PDSCH scheduled bythe PDCCH; and receiving, via a PUCCH or a PUSCH, HARQ-ACK informationcorresponding to the PDSCH, wherein PDCCH #C, PDCCH #G, and PDCCH #I aretransmitted, PDSCH #C is scheduled by the PDCCH #C, PDSCH #G isscheduled by the PDCCH #G, and PDSCH #I is scheduled by the PDCCH #I,the PDCCH #G indicates a second value, and the PDCCH #I indicates athird value, the PDCCH #I indicates transmission of at least HARQ-ACKinformation #I corresponding to the PDSCH #I on PUCCH #3, in a case thatthe second value and the third value are different from each other,HARQ-ACK information #G corresponding to the PDSCH #G and the HARQ-ACKinformation #I are multiplexed on the PUCCH #3, in a case that thesecond value is equal to the third value, HARQ-ACK information #Ccorresponding to the PDSCH #C, the HARQ-ACK information #G, and theHARQ-ACK information #I are multiplexed on the PUCCH #3, the HARQ-ACKinformation #G is new transmission on the PUCCH #3, and the HARQ-ACKinformation #C is retransmission on the PUCCH #3.

(8) An eighth aspect of the present invention is a communication methodused for a base station apparatus, the communication method includingthe steps of transmitting a PDCCH and transmitting a PDSCH scheduled bythe PDCCH, wherein based at least on the PDCCH, a PDSCH group ID and atoggle bit corresponding to the PDSCH group ID are indicated, in a casethat the toggle bit is toggled, HARQ-ACK information being alreadyreported (the HARQ-ACK information other than HARQ-ACK information notbeing reported yet) is deleted from an HARQ-ACK codebook correspondingto the PDSCH group ID, and the HARQ-ACK information corresponding to thePDSCH scheduled by the PDCCH is included in the HARQ-ACK codebook.

Advantageous Effects of Invention

According to an aspect of the present invention, the terminal apparatuscan efficiently perform communication. The base station apparatus canefficiently perform communication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual diagram of a radio communication system accordingto an aspect of the present embodiment.

FIG. 2 is an example illustrating a relationship of N^(slot) _(symb), asubcarrier spacing configuration μ, a slot configuration, and a CPconfiguration according to an aspect of the present embodiment.

FIG. 3 is a schematic diagram illustrating an example of a resource gridin a subframe according to an aspect of the present embodiment.

FIG. 4 is a diagram illustrating an example of monitoring occasions ofsearch space sets according to an aspect of the present embodiment.

FIG. 5 is a schematic block diagram illustrating a configuration of aterminal apparatus 1 according to an aspect of the present embodiment.

FIG. 6 is a schematic block diagram illustrating a configuration of abase station apparatus 3 according to an aspect of the presentembodiment.

FIG. 7 is a diagram illustrating a correspondence example between themonitoring occasion for the search space set (Monitoring occasion forsearch space set) and the monitoring occasion for a PDCCH (Monitoringoccasion for PDCCH) according to an aspect of the present embodiment.

FIG. 8 is a diagram illustrating an example of a procedure ofconfiguration of an HARQ-ACK codebook according to an aspect of thepresent embodiment.

FIG. 9 is a diagram illustrating an example of a procedure ofconfiguration of an HARQ-ACK codebook according to an aspect of thepresent embodiment.

FIG. 10 is a diagram illustrating an example of a procedure ofconfiguration of an HARQ-ACK codebook according to an aspect of thepresent embodiment.

FIG. 11 is a diagram illustrating an example of reporting of HARQ-ACKinformation according to an aspect of the present embodiment.

FIG. 12 is an example illustrating a toggle state of an NFI bitaccording to an aspect of the present embodiment.

FIG. 13 is an example of reporting of the HARQ-ACK information in a casethat the NFI bit corresponding to a certain PDSCH group is toggledaccording to an aspect of the present embodiment.

FIG. 14 is an example of reporting of the HARQ-ACK information in a casethat the NFI bit corresponding to a certain PDSCH group is not toggledaccording to an aspect of the present embodiment.

DESCRIPTION OF EMBODIMENTS

An embodiment of the present invention will be described below.

“A and/or B” may be a term including “A”, “B”, or “A and B”.

The fact that a parameter or information indicates one or multiplevalues may mean that the parameter or the information includes at leasta parameter or information indicating the one or the multiple values. Ahigher layer parameter may be a single higher layer parameter. Thehigher layer parameter may be an Information Element (IE) includingmultiple parameters.

FIG. 1 is a conceptual diagram of a radio communication system accordingto an aspect of the present embodiment. In FIG. 1 , the radiocommunication system includes terminal apparatuses 1A to 1C and a basestation apparatus 3. Hereinafter, each of the terminal apparatuses 1A to1C is also referred to as a terminal apparatus 1.

The base station apparatus 3 may include one of or both a Master CellGroup (MCG) and a Secondary Cell Group (SCG). The MCG is a group ofserving cells at least including a Primary Cell (PCell). The SCG is agroup of serving cells including at least a Primary Secondary Cell(PSCell). The PCell may be a serving cell that is given based on initialconnection. The MCG may include one or multiple Secondary Cells(SCells). The SCG may include one or multiple SCells. A serving cellidentity is a short identity for identifying the serving cell. Theserving cell identity may be provided by a higher layer parameter.

In the following, frame configuration will be described.

In the radio communication system according to an aspect of the presentembodiment, Orthogonal Frequency Division Multiplex (OFDM) is at leastused. An OFDM symbol is a unit of OFDM in the time domain. The OFDMsymbol at least includes one or multiple subcarriers. The OFDM symbolmay be converted into a time-continuous signal in baseband signalgeneration.

A SubCarrier Spacing (SCS) may be provided by a subcarrier spacingΔf=2^(μ)·15 kHz. For example, a subcarrier spacing configuration μ maybe configured to be any of 0, 1, 2, 3, 4, and/or 5. For a certainBandWidth Part (BWP), the subcarrier spacing configuration μ may beprovided by a higher layer parameter.

In the radio communication system according to an aspect of the presentembodiment, a time unit T_(c) is used for representing a length of thetime domain. The time unit T_(c) may be given byT_(c)=1/(Δf_(max)·N_(f)). Δf_(max) may be the maximum value of thesubcarrier spacing supported by the radio communication system accordingto an aspect of the present embodiment. Δf_(max) may be Δf_(max)=480kHz. N_(f) may be N_(f)=4096. A constant κ is κ=Δf_(max)·N_(f)/(Δf_(ref)N_(f,ref))=64. Δf_(ref) may be 15 kHz.N_(f,ref) may be 2048.

The constant κ may be a value indicating a relationship between areference subcarrier spacing and T_(c). The constant κ may be used forthe length of a subframe. Based at least on the constant κ, the numberof slots included in the subframe may be given. Δf_(ref) is thereference subcarrier spacing, and N_(f,ref) is a value corresponding tothe reference subcarrier spacing.

Downlink transmission and/or uplink transmission includes frames of 10ms. The frame includes 10 subframes. The length of the subframe is 1 ms.The length of the frame may be provided regardless of the subcarrierspacing Δf. In other words, the frame configuration may be providedregardless of μ. The length of the subframe may be provided regardlessof the subcarrier spacing Δf. In other words, the configuration of thesubframe may be provided regardless of μ.

For a certain subcarrier spacing configuration μ, the number and indexesof slots included in a subframe may be provided. For example, a firstslot number n^(μ) _(s) may be provided in ascending order ranging from 0to N^(subframe, μ) _(slot)−1 within a subframe. For the subcarrierspacing configuration μ, the number and indexes of slots included in aframe may be provided. For example, a second slot number n^(μ) _(s, f)may be provided in ascending order ranging from 0 to N^(frame, μ)_(slot)−1 within a frame. N^(slot) _(symb) continuous OFDM symbols maybe included in one slot. Ns^(l)'_(symb) may be provided based at leaston a part or an entirety of a slot configuration and/or a Cyclic Prefix(CP) configuration. The slot configuration may be provided at least by ahigher layer parameter tdd-UL-DL-ConfigurationCommon. The CPconfiguration may be provided based at least on a higher layerparameter. The CP configuration may be given based at least on dedicatedRRC signaling. Each of the first slot number and the second slot numberis also referred to as slot number (slot index).

FIG. 2 is an example illustrating a relationship of N^(slot) _(symb), asubcarrier spacing configuration μ, and a CP configuration according toan aspect of the present embodiment. In FIG. 2A, for example, thesubcarrier spacing configuration μ is two, and the CP configuration is anormal cyclic prefix (normal CP), N^(slot) _(symb)=14, N^(frame, μ)_(slot)=40, and N^(subframe, μ) _(slot)=4. In FIG. 2B, for example, thesubcarrier spacing configuration μ is two, and the CP configuration isan extended cyclic prefix (extended CP), N^(slot) _(symb)=12,N^(frame, μ) _(slot)=40, and N^(subframe, μ) _(slot)=4.

Physical resources will be described below.

An antenna port is defined in a manner in which a channel through whicha symbol is transmitted in one antenna port can be estimated from achannel through which another symbol is transmitted in the same antennaport. In a case that a large scale property of a channel through which asymbol is transmitted at one antenna port can be estimated from achannel through which a symbol is transmitted at another antenna port,the two antenna ports are referred to as Quasi Co-Located (QCL). Thelarge scale property may at least include long term performance of achannel The large scale property may at least include a part or all ofdelay spread, Doppler spread, Doppler shift, an average gain, an averagedelay, and a beam parameter (spatial Rx parameters). The fact that thefirst antenna port and the second antenna port are QCL with respect to abeam parameter may mean that a receive beam assumed by a receiver forthe first antenna port and a receive beam assumed by the receiver forthe second antenna port are the same. The fact that the first antennaport and the second antenna port are QCL with respect to a beamparameter may mean that a transmit beam assumed by a receiver for thefirst antenna port and a transmit beam assumed by the receiver for thesecond antenna port are the same. In a case that the large scaleproperty of a channel through which a symbol is transmitted in oneantenna port can be estimated from a channel through which a symbol istransmitted in another antenna port, the terminal apparatus 1 may assumethat the two antenna ports are QCL. The fact that two antenna ports areQCL may mean that it is assumed that the two antenna ports are QCL.

For each set of a subcarrier spacing configuration and a carrier, aresource grid including N^(μ) _(RB, x)N^(RB) _(sc) subcarriers andN^((μ)) _(symb)N^(subframe, μ) _(symb) OFDM symbols is provided. N^(μ)_(RB,x) may indicate the number of resource blocks provided for thesubcarrier spacing configuration μ for a carrier x. N^(μ) _(RB, x) mayindicate the maximum number of resource blocks provided for thesubcarrier spacing configuration μ for the carrier x. The carrier xindicates either a downlink carrier or an uplink carrier. In otherwords, x is “DL” or “UL”. N^(μ) _(RB) is a name including N^(μ)_(RB, DL) and/or N^(μ) _(RB, UL). N^(RB) _(sc) may indicate the numberof subcarriers included in one resource block. At least one resourcegrid may be provided for each antenna port p and/or for each subcarrierspacing configuration μ and/or for each Transmission directionconfiguration. The transmission direction at least includes a DownLink(DL) and an UpLink (UL). Hereinafter, a set of parameters including atleast some or all of the antenna port p, the subcarrier spacingconfiguration μ, and the transmission direction configuration is alsoreferred to as a first radio parameter set. In other words, one resourcegrid may be provided for each first radio parameter set.

In the downlink, a carrier included in a serving cell is referred to asa downlink carrier (or a downlink component carrier). In the uplink, acarrier included in a serving cell is referred to as an uplink carrier(uplink component carrier). A downlink component carrier and an uplinkcomponent carrier are collectively referred to as a component carrier(or a carrier).

Each element in the resource grid provided for each first radioparameter set is referred to as a resource element. The resource elementis identified by an index k_(sc) in the frequency domain and an indexl_(sym) in the time domain. For a certain first radio parameter set, theresource element is identified by the index k_(sc) in the frequencydomain and the index l_(sym) in the time domain The resource element tobe identified by the index k_(sc) of the frequency domain and the indexl_(sym) of the time domain is also referred to as a resource element(k_(sc), l_(sym)). The index k_(sc) of the frequency domain indicatesany value from 0 to N^(μ) _(RB)N^(RB) _(sc)−1. N^(μ) _(RB) may be thenumber of resource blocks provided for the subcarrier spacingconfiguration μ. N^(μ) _(RB) is the number of subcarriers included inthe resource block, and N^(RB) _(sc)=12. The index k_(sc) in thefrequency domain may correspond to the subcarrier index k_(sc). Theindex l_(sym) in the time domain may correspond to the OFDM symbol indexl_(sym).

FIG. 3 is a schematic diagram illustrating an example of the resourcegrid in the subframe according to an aspect of the present embodiment.In the resource grid of FIG. 3 , the horizontal axis is the indexl_(sym) in the time domain, and the vertical axis is the index k_(sc) inthe frequency domain. In one subframe, the frequency domain of theresource grid includes N^(μ) _(RB)N^(RB) _(sc) subcarriers. In onesubframe, the time domain of the resource grid may include 14·2^(μ) OFDMsymbols. One resource block includes N^(RB) _(sc) subcarriers. The timedomain of the resource block may correspond to 1 OFDM symbol. The timedomain of the resource block may correspond to 14 OFDM symbols. The timedomain of the resource block may correspond to one or multiple slots.The time domain of the resource block may correspond to one subframe.

For the terminal apparatus 1, performing transmission and/or receptionby using only a subset of resource grids may be indicated. The subset ofresource grids is also referred to as a BWP, and the BWP may be providedbased at least on a part or an entirety of the higher layer parameterand/or DCI. The BWP is also referred to as a bandwidth part (BP). Inother words, the terminal apparatus 1 may not receive an indication oftransmission and/or reception using all sets of resource grids. In otherwords, the terminal apparatus 1 may receive an indication oftransmission and/or reception using some frequency resources within theresource grid. One BWP may include multiple resource blocks in thefrequency domain. One BWP may include multiple contiguous resourceblocks in the frequency domain. A BWP configured for a downlink carrieris also referred to as a downlink BWP. A BWP configured for an uplinkcarrier is also referred to as an uplink BWP.

One or multiple downlink BWPs may be configured for the terminalapparatus 1. The terminal apparatus 1 may attempt to receive a physicalchannel (for example, a PDCCH, a PDSCH, and/or an SS/PBCH) in onedownlink BWP out of the one or multiple downlink BWPs. The one downlinkBWP is also referred to as an active downlink BWP.

One or multiple uplink BWPs may be configured for the terminal apparatus1. The terminal apparatus 1 may attempt to transmit a physical channel(for example, a PUCCH, a PUSCH, and/or a PRACH) in one uplink BWP out ofthe one or multiple uplink BWPs. The one uplink BWP is also referred toas an active uplink BWP.

A set of downlink BWPs may be configured for each serving cell. The setof downlink BWPs may include one or multiple downlink BWPs. A set ofuplink BWPs may be configured for each serving cell. The set of uplinkBWPs may include one or multiple uplink BWPs.

A higher layer parameter is a parameter included in a higher layersignaling. The higher layer signaling may be a Radio Resource Control(RRC) signaling, or may be a Medium Access Control Control Element (MACCE). Here, the higher layer signaling may be a signal of an RRC layer,or may be a signal of an MAC layer.

The higher layer signaling may be common RRC signaling. The common RRCsignaling may at least include a part or all of the following feature C1to feature C3. Feature C1) Being mapped to a BCCH logical channel or aCCCH logical channel

Feature C2) Including at least a radioResourceConfigCommon informationelement

Feature C3) Being mapped to a PBCH

The radioResourceConfigCommon information element may includeinformation indicating a configuration commonly used in a serving cell.The configuration used in a serving cell in common may at least includeconfiguration of the PRACH. The configuration of the PRACH may at leastindicate one or multiple random access preamble indexes. Theconfiguration of the PRACH may at least indicate time/frequencyresources of the PRACH.

The higher layer signaling may be dedicated RRC signaling. The dedicatedRRC signaling may at least include a part or all of the followingfeatures D1 to D2. Feature D1) Being mapped to a DCCH logical channel

Feature D2) Including at least a radioResourceConfigDedicatedinformation element

The radioResourceConfigDedicated information element may include atleast information indicating a configuration specific to the terminalapparatus 1. The radioResourceConfigDedicated information element mayinclude at least information indicating a BWP configuration. The BWPconfiguration may indicate at least a frequency resource of the BWP.

For example, a MIB, first system information, and second systeminformation may be included in the common RRC signaling. In addition, ahigher layer message that is mapped to the DCCH logical channel andincludes at least radioResourceConfigCommon may be included in thecommon RRC signaling. In addition, a higher layer message that is mappedto the DCCH logical channel and does not include theradioResourceConfigCommon information element may be included in thededicated RRC signaling. In addition, a higher layer message that ismapped to the DCCH logical channel and includes at least theradioResourceConfigDedicated information element may be included in thededicated RRC signaling.

The first system information may indicate at least a time index of aSynchronization Signal (SS) block. The SS block is also referred to asan SS/PBCH block. The SS/PBCH block is also referred to as an SS/PBCH.The first system information may include at least information related toa PRACH resource. The first system information may include at leastinformation related to a configuration of initial connection. The secondsystem information may be system information other than the first systeminformation.

The radioResourceConfigDedicated information element may include atleast information related to a PRACH resource. TheradioResourceConfigDedicated information element may include at leastinformation related to the configuration of initial connection.

In the following, physical channels and physical signals according tovarious aspects of the present embodiment will be described.

The uplink physical channel may correspond to a set of resource elementsfor carrying information that is generated in a higher layer. The uplinkphysical channel is a physical channel that is used in the uplinkcarrier. In the radio communication system according to an aspect of thepresent embodiment, at least a part or all of the following uplinkphysical channels are used.

Physical Uplink Control CHannel (PUCCH)

Physical Uplink Shared CHannel (PUSCH)

Physical Random Access CHannel (PRACH)

The PUCCH may be used to transmit Uplink Control Information (UCI). Theuplink control information includes some or all of Channel StateInformation (CSI), a Scheduling Request (SR), and a Hybrid AutomaticRepeat request ACKnowledgement (HARQ-ACK) corresponding to a transportblock (TB, a Medium Access Control Protocol Data Unit (MAC PDU),Downlink-Shared Channel (DL-SCH), and/or a Physical Downlink SharedChannel (PDSCH)).

The HARQ-ACK may include at least an HARQ-ACK bit corresponding at leastto one transport block. The HARQ-ACK bit may indicate an acknowledgement(ACK) or a negative-acknowledgement (NACK) corresponding to one ormultiple transport blocks. The HARQ-ACK may include at least an HARQ-ACKcodebook including one or multiple HARQ-ACK bits. The fact that theHARQ-ACK bit corresponds to one or multiple transport blocks may meanthat the HARQ-ACK bit corresponds to a PDSCH including the one or themultiple transport blocks. The HARQ-ACK bit may indicate an ACK or NACKcorresponding to one Code Block Group (CBG) included in the transportblock.

The Scheduling Request (SR) may be used at least for requesting aresource of a PUSCH for initial transmission. A scheduling request bitmay be used to indicate either a positive SR or a negative SR. Thescheduling request bit indicating the positive SR is also referred to as“the positive SR being transmitted”. The positive SR may indicate thatresources of the PUSCH for initial transmission are requested by theterminal apparatus 1. The positive SR may indicate that a schedulingrequest is triggered by the higher layer. The positive SR may betransmitted in a case that the higher layer indicates transmission ofthe scheduling request. The scheduling request bit indicating thenegative SR is also referred to as “the negative SR being transmitted”.The negative SR may indicate that resources of the PUSCH for initialtransmission are not requested by the terminal apparatus 1. The negativeSR may indicate that the scheduling request is not triggered by thehigher layer. The negative SR may be transmitted in a case thattransmission of a scheduling request is not indicated by the higherlayer.

Channel state information may include at least some or all of a ChannelQuality Indicator (CQI), a Precoder Matrix Indicator (PMI), and a RankIndicator (RI). The CQI is an indicator related to quality of a channel(for example, propagation intensity), and the PMI is an indicatorindicating a precoder. The RI is an indicator indicating a transmissionrank (or the number of transmission layers).

The PUCCH supports PUCCH formats (PUCCH formats 0 to 4). The PUCCHformats may be mapped to the PUCCH and may then be transmitted. ThePUCCH format may be transmitted on the PUCCH. The fact that the PUCCHformat is transmitted may mean that the PUCCH is transmitted.

The PUSCH may be used at least to transmit a transport block ((TB), theMAC PDU, a UL-SCH, and/or the PUSCH). The PUSCH may be used to transmitat least some or all of the transport block, the HARQ-ACK, the channelstate information, and the scheduling request. The PUSCH is used atleast to transmit a random access message 3.

The PRACH is used at least to transmit a random access preamble (randomaccess message 1). The PRACH may be used at least to indicate some orall of an initial connection establishment procedure, a handoverprocedure, a connection re-establishment procedure, synchronization forPUSCH transmission (timing adjustment), and a resource request for thePUSCH. The random access preamble may be used for notifying an index(random access preamble index) that is given by a higher layer of theterminal apparatus 1 to the base station apparatus 3.

In FIG. 1 , in uplink radio communication, the following uplink physicalsignals are used. The uplink physical signals need not be used fortransmitting information output from a higher layer, but are used by aphysical layer.

UpLink Demodulation Reference Signal (UL DMRS)

Sounding Reference Signal (SRS)

UpLink Phase Tracking Reference Signal (UL PTRS)

The UL DMRS is related to transmission of the PUSCH and/or the PUCCH.The UL DMRS is multiplexed on the PUSCH or the PUCCH. The base stationapparatus 3 may use the UL DMRS for performing channel compensation ofthe PUSCH or the PUCCH. In the following, concurrent transmission of thePUSCH and the UL DMRS related to the PUSCH is simply referred to astransmission of the PUSCH. In the following, concurrent transmission ofthe PUCCH and the UL DMRS related to the PUCCH is simply referred to astransmission of the PUCCH. The UL DMRS related to the PUSCH is alsoreferred to as the UL DMRS for the PUSCH. The UL DMRS related to thePUCCH is also referred to as the UL DMRS for the PUCCH.

The SRS need not be related to transmission of the PUSCH or the PUCCH.The base station apparatus 3 may use the SRS for measurement of achannel state. The SRS may be transmitted at the end of a subframe in anuplink slot or in a certain number of OFDM symbols from the end.

The UL PTRS may be a reference signal that is at least used for phasetracking. The UL PTRS may be related to a UL DMRS group at leastincluding an antenna port used for one or multiple UL DMRSs. The factthat the UL PTRS and the UL DMRS group are related to each other maymean that an antenna port of the UL PTRS and a part or all of antennaports included in the UL DMRS group are at least QCL. The UL DMRS groupmay be identified based at least on an antenna port having the smallestindex in the UL DMRSs included in the UL DMRS group. The UL PTRS may bemapped to an antenna port having the smallest index in one or multipleantenna ports to which one codeword is mapped. The UL PTRS may be mappedto the first layer in a case that one codeword is at least mapped to thefirst layer and the second layer. The UL PTRS need not be mapped to thesecond layer. The index of the antenna port to which the UL PTRS ismapped may be given based at least on downlink control information.

In FIG. 1 , in downlink radio communication from the base stationapparatus 3 to the terminal apparatus 1, the following downlink physicalchannels are used. The downlink physical channels are used by a physicallayer for transmitting information output from a higher layer.

Physical Broadcast Channel (PBCH)

Physical Downlink Control Channel (PDCCH)

Physical Downlink Shared Channel (PDSCH)

The PBCH is used at least to transmit a Master Information Block ((MIB),and/or a Broadcast Channel(BCH)). The PBCH may be transmitted based on aprescribed transmission interval. The PBCH may be transmitted at aninterval of 80 ms. The PBCH may be transmitted at intervals of 160 ms.Contents of information included in the PBCH may be updated at every 80ms. A part or an entirety of the information included in the PBCH may beupdated at every 160 ms. The PBCH may include 288 subcarriers. The PBCHmay include 2, 3, or 4 OFDM symbols. The MIB may include informationassociated with an identifier (index) of a synchronization signal. TheMIB may include information indicating at least a part of a number ofthe slot, a number of a subframe, and/or a number of a radio frame inwhich the PBCH is transmitted.

The PDCCH is used at least to transmit Downlink Control Information(DCI). The PDCCH may be transmitted with at least the downlink controlinformation included therein. The PDCCH may include the downlink controlinformation. The downlink control information is also referred to as aDCI format. The downlink control information may include at least eithera downlink grant or an uplink grant. The DCI format used for schedulingthe PDSCH is also referred to as a downlink DCI format. The DCI formatused for scheduling the PUSCH is also referred to as an uplink DCIformat. The downlink grant is also referred to as downlink assignment ordownlink allocation. The uplink DCI format at least includes one or bothof DCI format 0_0 and DCI format 0_1.

DCI format 0_0 includes at least some or all of 1A to 1F.

-   1A) DCI format identification field (Identifier for DCI formats    field)-   1B) Frequency domain resource allocation field (Frequency domain    resource assignment field)-   1C) Time domain resource allocation field (Time domain resource    assignment field)-   1D) Frequency hopping flag field-   1E) Modulation and Coding Scheme field (MCS field)

The DCI format specification field may be used at least to indicatewhich of one or multiple DCI formats the DCI format including the DCIformat specification field corresponds to. The one or multiple DCIformats may be given based at least on a part or all of DCI format 1_0,DCI format 1_1, DCI format 0_0, and/or DCI format 0_1.

The frequency domain resource assignment field may be used at least toindicate assignment of a frequency resource for the PUSCH scheduled bythe DCI format including the frequency domain resource assignment field.The frequency domain resource assignment field is also referred to asFrequency Domain Resource Allocation (FDRA) field.

The time domain resource assignment field may be used at least toindicate assignment of a time resource for the PUSCH scheduled by theDCI format including the time domain resource assignment field.

The frequency hopping flag field may be used at least to indicatewhether frequency hopping is to be applied to the PUSCH scheduled by theDCI format including the frequency hopping flag field.

The MCS field may be used at least to indicate some or all of amodulation scheme for the PUSCH scheduled by the DCI format includingthe MCS field and/or a target coding rate. The target coding rate may bea target coding rate for a transport block of the PUSCH. The size of thetransport block (Transport Block Size (TBS)) may be provided based atleast on the target coding rate.

DCI format 0_1 includes at least some or all of 2A to 2G.

-   2A) DCI format identification field-   2B) Frequency domain resource allocation field-   2C) Time domain resource allocation field-   2D) Frequency hopping flag field-   2E) MCS field-   2F) CSI request field-   2G) BWP field-   2H) First UL DAI field (1^(st) downlink assignment index)-   2I) Second UL DAI field (2^(nd) downlink assignment index)

The first UL DAI field is used at least for indicating a transmissionstate of the PDSCH. In a case that a Dynamic HARQ-ACK codebook is used,the size of the first UL DAI field may be 2 bits.

The second UL DAI field is used at least for indicating a transmissionstate of the PDSCH. In a case that the dynamic HARQ-ACK codebookincluding two sub-codebooks is used, the size of the second UL DAI fieldmay be 2 bits.

The BWP field may be used for indicating an uplink BWP to which thePUSCH that is scheduled by DCI format 0_1 is mapped.

The CSI request field is at least used for indicating the report of theCSI. The size of the CSI request field may be given based at least on ahigher layer parameter ReportTriggerSize.

The downlink DCI format at least includes one or both of DCI format 1_0and DCI format

DCI format 1_0 includes at least some or all of 3A to 3H.

-   3A) DCI format identification field (Identifier for DCI formats    field)-   3B) Frequency domain resource allocation field (Frequency domain    resource assignment field)-   3C) Time domain resource allocation field (Time domain resource    assignment field)-   3D) Frequency hopping flag field-   3E) Modulation and Coding Scheme field (MCS field)-   3F) First CSI request field (First CSI request field)-   3G) PDSCH-to-HARQ feedback timing indicator field-   3H) PUCCH resource indication field (PUCCH resource indicator field)

The timing indicator field from the PDSCH to the HARQ feedback may be afield indicating a timing K1. In a case that the index of the slotincluding the last OFDM symbol of the PDSCH is a slot n, the index ofthe slot including the PUCCH or the PUSCH including at least HARQ-ACKcorresponding to the transport block included in the PDSCH may be n+K1.In a case that the index of the slot including the last OFDM symbol ofthe PDSCH is a slot n, the index of the slot including the OFDM symbolat the head of the PUCCH or the OFDM symbol at the head of the PUSCHincluding at least HARQ-ACK corresponding to the transport blockincluded in the PDSCH may be n+K1.

The PDSCH-to-HARQ feedback timing indicator field(PDSCH-to-HARQ_feedback timing indicator field) may be hereinafterreferred to as an HARQ indicator field.

The PUCCH resource indicator field may be a field indicating indexes ofone or multiple PUCCH resources included in the PUCCH resource set.

DCI format 1_1 includes at least some or all of 4A to 4J.

-   4A) DCI format specification field (Identifier for DCI formats    field)-   4B) Frequency domain resource allocation field (Frequency domain    resource assignment field)-   4C) Time domain resource assignment field-   4D) Frequency hopping flag field-   4E) Modulation and Coding Scheme field (MCS field)-   4F) First CSI request field-   4G) PDSCH-to-HARQ feedback timing indicator field-   4H) PUCCH resource indicator field-   4J) BWP field-   4K) PGI field (PDSCH Group Indicator field)-   4L) RPG field (Requested PDSCH Group field)-   4M) NFI field (New Feedback Indicator field)

The BWP field may be used to indicate the downlink BWP to which thePDSCH scheduled by DCI format 1_1 is mapped.

The PGI field, the RPG field, and the NFI field will be described later.

DCI format 2_0 may at least include one or multiple Slot FormatIndicators (SFIs).

Each DCI format (DCI format 1_0, DCI format 1_1, DCI format 0_0, and/orDCI format 0_1 DCI format 1_1) may include a field different from thefields described above.

In various aspects of the present embodiment, the number of resourceblocks indicates the number of resource blocks in the frequency domainunless otherwise specified.

The downlink grant is used at least for scheduling a single PDSCH in asingle serving cell.

The uplink grant is used at least for scheduling a single PUSCH in asingle serving cell.

One physical channel may be mapped to one serving cell. A singlephysical channel may be mapped to a single BWP configured to a singlecarrier included in a single serving cell.

In the terminal apparatus 1, one or multiple COntrol REsource SETs(CORESETs) may be configured. The terminal apparatus 1 monitors thePDCCH in the one or multiple control resource sets. Here, monitoring ofthe PDCCH in the one or multiple control resource sets may includemonitoring of one or multiple PDCCHs corresponding to the one ormultiple control resource sets, respectively. Note that the PDCCH mayinclude a set of one or multiple PDCCH candidates and/or one or multiplePDCCH candidates. Also, monitoring of the PDCCH may include monitoringand detecting the PDCCH and/or a DCI format transmitted via the PDCCH.

The control resource set may indicate a time-frequency domain to whichone or multiple PDCCHs can be mapped. The control resource set may be anarea in which the terminal apparatus 1 monitors the PDCCH. The controlresource set may include continuous resources (Localized resources). Thecontrol resource set may include non-continuous resources (distributedresources).

In the frequency domain, the unit of mapping of the control resource setmay be a resource block. In the frequency domain, for example, the unitof mapping of the control resource set may be six resource blocks. Inthe time domain, the unit of mapping of the control resource set may bean OFDM symbol. In the time domain, for example, the unit of mapping ofthe control resource set may be one OFDM symbol.

Mapping of the control resource set to the resource block may beprovided based at least on the higher layer parameter. The higher layerparameter may include a bitmap for a Resource Block Group (RBG). Theresource block group may be provided by six continuous resource blocks.

The number of OFDM symbols included in the control resource set may beprovided based at least on the higher layer parameter.

A certain control resource set may be a Common control resource set. Thecommon control resource set may be a control resource set configuredcommonly to multiple terminal apparatuses 1. The common control resourceset may be provided at least based on some or all of the MIB, the firstsystem information, the second system information, the common RRCsignaling, and a cell ID. For example, the time resource and/or thefrequency resource of the control resource set configured to monitor thePDCCH to be used for scheduling the first system information may beprovided based at least on the MIB.

The control resource set configured by the MIB is also referred to asCORESET#0. CORESET#0 may be a control resource set of index#0.

A certain control resource set may be a Dedicated control resource set.The dedicated control resource set may be a control resource setconfigured to be used exclusively for the terminal apparatus 1. Thededicated control resource set may be provided based at least on some orall of the dedicated RRC signaling and values of C-RNTI. Multiplecontrol resource sets may be configured for the terminal apparatus 1,and an index (control resource set index) may be provided for each ofthe control resource sets. One or more control channel elements (CCEs)may be configured in the control resource set, and an index (CCE index)may be provided for each of the CCEs.

A set of candidates of the PDCCH monitored by the terminal apparatus 1may be defined from the perspective of a search space. In other words,the set of PDCCH candidates monitored by the terminal apparatus 1 may begiven by a search space.

The search space may include one or multiple PDCCH candidates of one ormultiple Aggregation levels. The aggregation level of the PDCCHcandidates may indicate the number of CCEs constituting the PDCCH. ThePDDCH candidate may be mapped to one or multiple CCEs.

The terminal apparatus 1 may monitor at least one or multiple searchspaces in the slot in which DRX (Discontinuous reception) is notconfigured. The DRX may be provided based at least on a higher layerparameter. The terminal apparatus 1 may monitor at least one or multipleSearch space sets in the slot in which DRX is not configured. Multiplesearch space sets may be configured for the terminal apparatus 1. Anindex (search space set index) may be provided for each of the searchspace sets.

The search space set may at least include one or multiple search spaces.An index (search space index) may be provided for each of the searchspaces.

Each search space set may be associated at least with one controlresource set. Each search space set may be included in one controlresource set. For each of the search space sets, the index of thecontrol resource set related to the search space set may be given.

For each of the search space sets, a monitoring interval (Monitoringperiodicity) of the search space set may be configured. The monitoringinterval of the search space set may at least indicate the interval ofthe slot in which monitoring of the search space set is performed by theterminal apparatus 1. A higher layer parameter at least indicating themonitoring interval of the search space set may be given for each searchspace set.

For each of the search space sets, a Monitoring offset of the searchspace set may be configured. The monitoring offset of the search spaceset may at least indicate an offset from a reference index (for example,slot #0) of an index of a slot in which monitoring of the search spaceset is performed by the terminal apparatus 1. A higher layer parameterat least indicating the monitoring offset of the search space set may begiven for each search space set.

For each of the search space sets, a Monitoring pattern of the searchspace set may be configured. The monitoring pattern of the search spaceset may indicate the first OFDM symbol for the search space set in whichmonitoring is performed. The monitoring pattern of the search space setmay be given by a bitmap indicating the first OFDM symbol in one ormultiple slots. A higher layer parameter at least indicating themonitoring pattern of the search space set may be given for each searchspace set.

A Monitoring occasion for the search space set may be given based atleast on a part or all of the monitoring interval of the search spaceset, the monitoring offset of the search space set, the monitoringpattern of the search space set, and/or configuration of DRX.

FIG. 4 is a diagram illustrating an example of the monitoring occasionfor the search space set according to an aspect of the presentembodiment. In FIG. 4 , a search space set 91 and a search space set 92are configured in a primary cell 301, a search space set 93 isconfigured in a secondary cell 302, and a search space set 94 isconfigured in a secondary cell 303.

In FIG. 4 , each block hatched with grid lines represents the searchspace set 91, each block hatched with lines rising diagonally up and tothe right represents the search space set 92, each block hatched withlines rising diagonally up and to the left represents the search spaceset 93, and each block hatched with horizontal lines represents thesearch space set 94.

The monitoring interval of the search space set 91 is set to one slot,the monitoring offset of the search space set 91 is set to zero slots,and the monitoring pattern of the search space set 91 is set to [1, 0,0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0]. In other words, the monitoringoccasion for the search space set 91 is the first OFDM symbol (OFDMsymbol #0) and the eighth OFDM symbol (OFDM symbol #7) in each of theslots.

The monitoring interval of the search space set 92 is set to two slots,the monitoring offset of the search space set 92 is set to zero slots,and the monitoring pattern of the search space set 92 is set to [1, 0,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]. In other words, the monitoringoccasion for the search space set 92 is the first OFDM symbol (OFDMsymbol #0) in each of the even-numbered slots.

The monitoring interval of the search space set 93 is set to two slots,the monitoring offset of the search space set 93 is set to zero slots,and the monitoring pattern of the search space set 93 is set to [0, 0,0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0]. In other words, the monitoringoccasion for the search space set 93 is the eighth OFDM symbol (OFDMsymbol #7) in each of the even-numbered slots.

The monitoring interval of the search space set 94 is set to two slots,the monitoring offset of the search space set 94 is set to one slot, andthe monitoring pattern of the search space set 94 is set to [1, 0, 0, 0,0, 0, 0, 0, 0, 0, 0, 0, 0, 0]. In other words, the monitoring occasionfor the search space set 94 is the first OFDM symbol (OFDM symbol #0) ineach of the odd-numbered slots.

The physical resources of the search space include configuration units(Control Channel Elements (CCEs)) of a control channel The CCE includesa prescribed number of Resource Element Groups (REGs). For example, theCCE may include six REGs. The REG may include one Physical ResourceBlock (PRB) during one OFDM symbol. In other words, the REG may include12 Resource Elements (REs). The PRB is also simply referred to as aResource Block (RB).

The PDSCH is used at least to transmit the transport block. The PDSCHmay be used at least to transmit a random access message 2 (randomaccess response). The PDSCH may be used at least to transmit systeminformation including parameters used for initial access.

In FIG. 1 , in downlink radio communication, the following downlinkphysical signals are used. The downlink physical signals need not beused for transmitting information output from a higher layer, but areused by a physical layer.

Synchronization signal (SS)

DownLink DeModulation Reference Signal (DL DMRS)

Channel State Information-Reference Signal (CSI-RS)

DownLink Phase Tracking Reference Signal (DL PTRS)

The synchronization signal is used by the terminal apparatus 1 toestablish synchronization with a downlink frequency domain and/or timedomain The synchronization signal includes a Primary SynchronizationSignal (PSS) and a Secondary Synchronization Signal (SSS).

An SS block (SS/PBCH block) includes at least some or all of the PSS,the SSS, and the PBCH.

The DL DMRS is related to transmission of the PBCH, the PDCCH, and/orthe PDSCH. The DL DMRS is multiplexed on the PBCH, the PDCCH, and/or thePDSCH. In order to channel compensation of the PBCH, the PDCCH, or thePDSCH, the terminal apparatus 1 may use the DL DMRS corresponding to thePBCH, the PDCCH, or the PDSCH.

The CSI-RS may be a signal used at least to calculate channel stateinformation. A pattern of the CSI-RS assumed by the terminal apparatusmay be provided at least by a higher layer parameter.

The PTRS may be a signal that is at least used for compensation of phasenoise. A pattern of the PTRS assumed by the terminal apparatus may beprovided based at least on a higher layer parameter and/or the DCI.

The DL PTRS may be related to the DL DMRS group at least including anantenna port used for one or multiple DL DMRSs.

The downlink physical channel and the downlink physical signal are alsocollectively referred to as the downlink signal. The uplink physicalchannel and the uplink physical signal are also collectively referred toas the uplink signal. The downlink signal and the uplink signal are alsocollectively referred to as the physical signal. The downlink signal andthe uplink signal are also collectively referred to as the signal. Thedownlink physical channel and the uplink physical channel arecollectively referred to as the physical channel. The downlink physicalsignal and the uplink physical signal are collectively referred to asthe physical signal.

A Broadcast CHannel (BCH), an Uplink-Shared CHannel (UL-SCH), and aDownlink-Shared CHannel (DL-SCH) are transport channels. A channel usedin a Medium Access Control (MAC) layer is referred to as a transportchannel A unit of the transport channel used in the MAC layer is alsoreferred to as a transport block (TB) or an MAC PDU. Control of theHybrid Automatic Repeat reQuest (HARQ) is performed for each transportblock in the MAC layer. The transport block is a unit of data that theMAC layer delivers to the physical layer. In the physical layer, thetransport block is mapped to a codeword, and modulation processing isperformed for each codeword.

The base station apparatus 3 and the terminal apparatus 1 exchange(transmit and/or receive) a higher layer signaling in a higher layer.For example, the base station apparatus 3 and the terminal apparatus 1may transmit and/or receive, in a Radio Resource Control (RRC) layer,RRC signaling (a Radio Resource Control (RRC) message and/or RadioResource Control (RRC) information). The base station apparatus 3 andthe terminal apparatus 1 may transmit and/or receive a MAC ControlElement (CE) in the MAC layer. Here, the RRC signaling and/or the MAC CEis also referred to as a higher layer signaling.

The PUSCH and the PDSCH may be at least used for transmitting the RRCsignaling and/or the MAC CE. Here, the RRC signaling transmitted on thePDSCH from the base station apparatus 3 may be signaling that is commonto multiple terminal apparatuses 1 in a serving cell. The signalingcommon to the multiple terminal apparatuses 1 in the serving cell isalso referred to as common RRC signaling. The RRC signaling transmittedfrom the base station apparatus 3 through the PDSCH may be signalingdedicated to a certain terminal apparatus 1 (also referred to asdedicated signaling or UE specific signaling). The signaling dedicatedto the terminal apparatus 1 is also referred to as dedicated RRCsignaling. A serving cell-specific higher layer parameter may betransmitted using the signaling common to the multiple terminalapparatuses 1 in the serving cell or the signaling dedicated to acertain terminal apparatus 1. A UE-specific higher layer parameter maybe transmitted using signaling dedicated to a certain terminal apparatus1.

A Broadcast Control CHannel (BCCH), a Common Control CHannel (CCCH), anda Dedicated Control CHannel (DCCH) are logical channels. For example,the BCCH is a channel of a higher layer that is used for transmittingthe MIB. The Common Control CHannel (CCCH) is a channel of a higherlayer that is used for transmitting common information in multipleterminal apparatuses 1. Here, the CCCH may be, for example, used for theterminal apparatus 1 that is not in a state of RRC connection. TheDedicated Control CHannel (DCCH) is a channel of a higher layer that isat least used for transmitting control information (dedicated controlinformation) that is dedicated to the terminal apparatus 1. Here, theDCCH may be, for example, used for the terminal apparatus 1 that is in astate of RRC connection.

The BCCH in the logical channel may be mapped to the BCH, the DL-SCH, orthe UL-SCH in the transport channel The CCCH in the logical channel maybe mapped to the DL-SCH or the UL-SCH in the transport channel The DCCHin the logical channel may be mapped to the DL-SCH or the UL-SCH in thetransport channel

The UL-SCH in the transport channel may be mapped to the PUSCH in thephysical channel The DL-SCH in the transport channel may be mapped tothe PDSCH in the physical channel The BCH in the transport channel maybe mapped to the PBCH in the physical channel.

In the following, a configuration example of the terminal apparatus 1according to an aspect of the present embodiment will be described.

FIG. 5 is a schematic block diagram illustrating a configuration of theterminal apparatus 1 according to an aspect of the present embodiment.As illustrated in the figure, the terminal apparatus 1 includes a radiotransmission and/or reception unit 10 and a higher layer processing unit14. The radio transmission and/or reception unit 10 at least includes apart or all of an antenna unit 11, a Radio Frequency (RF) unit 12, and abaseband unit 13. The higher layer processing unit 14 at least includesa part or all of a medium access control layer processing unit 15 and aradio resource control layer processing unit 16. The radio transmissionand/or reception unit 10 is also referred to as a transmitter, areceiver, or a physical layer processing unit.

The higher layer processing unit 14 outputs uplink data (transportblock) generated by a user operation or the like to the radiotransmission and/or reception unit 10. The higher layer processing unit14 performs processing of an MAC layer, a Packet Data ConvergenceProtocol (PDCP) layer, a Radio Link Control (RLC) layer, and an RRClayer.

The medium access control layer processing unit 15 included in thehigher layer processing unit 14 performs processing of the MAC layer.

The radio resource control layer processing unit 16 included in thehigher layer processing unit 14 performs processing of the RRC layer.The radio resource control layer processing unit 16 performs managementof various pieces of configuration information/parameters of itsapparatus. The radio resource control layer processing unit 16 setsvarious pieces of configuration information/parameters, based on ahigher layer signaling received from the base station apparatus 3.Specifically, the radio resource control layer processing unit 16 setsvarious pieces of configuration information/parameters, based oninformation indicating the various pieces of configurationinformation/parameters received from the base station apparatus 3. Notethat the configuration information may include information related tothe processing or configurations of the physical channel, the physicalsignal (that is, the physical layer), the MAC layer, the PDCP layer, theRLC layer, and the RRC layer. The parameters may be higher layerparameters.

The radio transmission and/or reception unit 10 performs processing ofthe physical layer, such as modulation, demodulation, coding, anddecoding. The radio transmission and/or reception unit 10 separates,demodulates, and decodes a received physical signal, and outputs thedecoded information to the higher layer processing unit 14. The radiotransmission and/or reception unit 10 generates a physical signal byperforming modulation and coding of data and generating a basebandsignal (conversion into a time-continuous signal) and transmits thephysical signal to the base station apparatus 3.

The RF unit 12 converts (down converts) a signal received via theantenna unit 11 into a baseband signal by orthogonal demodulation andremoves unnecessary frequency components. The RF unit 12 outputs aprocessed analog signal to the baseband unit.

The baseband unit 13 converts the analog signal input from the RF unit12 into a digital signal. The baseband unit 13 removes a portioncorresponding to a Cyclic Prefix (CP) from the converted digital signal,performs a Fast Fourier Transform (FFT) on the signal from which the CPhas been removed, and extracts a signal in the frequency domain.

The baseband unit 13 generates an OFDM symbol by performing Inverse FastFourier Transform (IFFT) on the data, adds CP to the generated OFDMsymbol, generates a baseband digital signal, and converts the basebanddigital signal into an analog signal. The baseband unit 13 outputs theconverted analog signal to the RF unit 12.

The RF unit 12 removes unnecessary frequency components from the analogsignal input from the baseband unit 13 through a low-pass filter, upconverts the analog signal into a signal of a carrier frequency, andtransmits the up converted signal via the antenna unit 11. The RF unit12 amplifies power. The RF unit 12 may have a function of controllingtransmission power. The RF unit 12 is also referred to as a transmissionpower control unit.

In the following, a configuration example of the base station apparatus3 according to an aspect of the present embodiment will be described.

FIG. 6 is a schematic block diagram illustrating a configuration of thebase station apparatus 3 according to an aspect of the presentembodiment. As illustrated in the figure, the base station apparatus 3includes a radio transmission and/or reception unit 30 and a higherlayer processing unit 34. The radio transmission and/or reception unit30 includes an antenna unit 31, an RF unit 32, and a baseband unit 33.The higher layer processing unit 34 includes a medium access controllayer processing unit 35 and a radio resource control layer processingunit 36. The radio transmission and/or reception unit 30 is alsoreferred to as a transmitter, a receiver, or a physical layer processingunit.

The higher layer processing unit 34 performs processing of an MAC layer,a PDCP layer, an RLC layer, and an RRC layer.

The medium access control layer processing unit 35 included in thehigher layer processing unit 34 performs processing of the MAC layer.

The radio resource control layer processing unit 36 included in thehigher layer processing unit 34 performs processing of the RRC layer.The radio resource control layer processing unit 36 generates, oracquires from a higher node, downlink data (transport block) mapped to aPDSCH, system information, an RRC message, an MAC CE, and the like, andoutputs the data to the radio transmission and/or reception unit 30. Theradio resource control layer processing unit 36 performs management ofvarious pieces of configuration information/parameters of each of theterminal apparatuses 1. The radio resource control layer processing unit36 may set various pieces of configuration information/parameters foreach of the terminal apparatuses 1 through a higher layer signaling.Specifically, the radio resource control layer processing unit 36transmits or broadcasts information indicating the various pieces ofconfiguration information/parameters. Note that the configurationinformation may include information related to the processing orconfigurations of the physical channel, the physical signal (that is,the physical layer), the MAC layer, the PDCP layer, the RLC layer, andthe RRC layer. The parameters may be higher layer parameters.

The functionality of the radio transmission and/or reception unit 30 issimilar to the functionality of the radio transmission and/or receptionunit 10, and description thereof will thus be omitted.

Each of the units denoted by the reference sign 10 to the reference sign16 included in the terminal apparatus 1 may be configured as a circuit.Each of the units denoted by the reference sign 30 to the reference sign36 included in the base station apparatus 3 may be configured as acircuit.

The terminal apparatus 1 may perform Carrier sense prior to transmissionof a physical signal. Also, the base station apparatus 3 may performcarrier sense prior to transmission of a physical signal. The carriersense may be to perform Energy detection on a Radio channel. Whether thephysical signal can be transmitted may be provided based on the carriersense performed prior to transmission of the physical signal. In a casethat the amount of energy detected in carrier sense performed prior totransmission of a physical signal is greater than a prescribed thresholdvalue, for example, the transmission of the physical channel may not beperformed, or it may be determined that the transmission is notpossible. Also, in a case that the amount of energy detected in thecarrier sense performed prior to the transmission of the physical signalis smaller than the prescribed threshold value, the transmission of thephysical channel may be performed, or it may be determined that thetransmission is possible. Moreover, in a case that the amount of energydetected in the carrier sense performed prior to the transmission of thephysical signal is equal to the prescribed threshold value, thetransmission of the physical channel may be performed or may not beperformed. In other words, in a case that the amount of energy detectedin the carrier sense performed prior to the transmission of the physicalsignal is equal to the prescribed threshold value, it may be determinedthat the transmission is not possible, or it may be determined that thetransmission is possible.

A procedure in which whether the transmission of the physical channel ispossible based on the carrier sense is also referred to as Listen BeforeTalk (LBT). A situation in which the transmission of the physical signalis determined to be not possible as a result of the LBT is also referredto as a busy state or busy. For example, the busy state may be a statein which the amount of energy detected in the carrier sense is greaterthan the prescribed threshold value. In addition, the situation in whichthe transmission of the physical signal is determined to be possible asa result of the LBT is also referred to as an idle state or idle. Forexample, the idle state may be a state in which the amount of energydetected in the carrier sense is smaller than the prescribed thresholdvalue.

The terminal apparatus 1 may multiplex uplink control information (UCI)to the PUCCH and transmit the PUCCH. The terminal apparatus 1 maymultiplex the UCI to the PUSCH and transmit the PUSCH. The UCI mayinclude at least one of downlink Channel State Information (CSI), aScheduling Request (SR) indicating a request for a PUSCH resource, and aHybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) for downlinkdata (a Transport block, a Medium Access Control Protocol Data Unit (MACPDU), a Downlink-Shared Channel (DL-SCH), and/or a Physical DownlinkShared Channel (PDSCH)).

HARQ control for one transport block (TB) may be referred to as an HARQprocess. The HARQ control is capable of parallel operation for multipletransport blocks (TBs). Each HARQ process may be associated with an HARQprocess identifier.

FIG. 7 is a diagram illustrating a correspondence example between themonitoring occasion for the search space set (Monitoring occasion forsearch space set) and the monitoring occasion for the PDCCH (Monitoringoccasion for PDCCH) according to an aspect of the present embodiment. InFIG. 7 , the monitoring occasion for the search space set in the primarycell is the first OFDM symbol of the slot, and the monitoring occasionfor the search space set in the secondary cell is the first OFDM symbolof the slot and the intermediate OFDM symbol (for example, OFDM symbol#7) of the slot. In FIG. 7 , the monitoring occasion for the PDCCHcorresponds to the first OFDM symbol of slot #n and the intermediateOFDM symbol of slot #n, and the first OFDM symbol of slot #n+1 and theintermediate OFDM symbol of slot #n+1. In other words, the monitoringoccasion for the PDCCH may be defined as an occasion in which themonitoring occasion for the search space set is configured for at leastone of one or multiple serving cells. The monitoring occasion for thePDCCH may correspond to an index of the OFDM symbol for which themonitoring occasion for the search space set is configured for at leastone of one or multiple serving cells.

In the slot, the monitoring occasion for the search space set startedfrom a certain OFDM symbol index may correspond to the monitoringoccasion for the PDCCH started from the certain OFDM symbol index. Themonitoring occasion for the PDCCH started from a certain OFDM symbolindex may correspond to each monitoring occasion for the search spaceset started from the certain OFDM symbol index.

FIG. 8 , FIG. 9 , and FIG. 10 are diagrams illustrating an example of aprocedure of configuration of a codebook (HARQ-ACK codebook) of theHARQ-ACK information according to an aspect of the present embodiment.<AX> of FIG. 8 , FIG. 9 , and FIG. 10 is also referred to as step AX. InFIG. 8 , FIG. 9 , and FIG. 10 , “A=B” may mean that A is set to B. InFIG. 8 , FIG. 9 , and FIG. 10 , “A=B” may mean that B is input to A. Theterminal apparatus 1 generates the codebook (HARQ-ACK codebook) of theHARQ-ACK information, based on the procedure illustrated in FIG. 8 ,FIG. 9 , and FIG. 10 .

The codebook of the HARQ-ACK information may be given based at least ona part or all of step A1 to step A46.

The codebook of the HARQ-ACK information may be given based at least ona part or all of a set of monitoring occasions for the PDCCH, a value ofa UL DAI field, a value of a counter DAI field, and/or a DAI field.

The codebook of the HARQ-ACK information may be given based at least ona part or all of a set of monitoring occasions for the PDCCH, a UL DAI,a counter DAI, and/or a total DAI.

In step A1, a serving cell index c is set to 0. The serving cell indexmay be given based at least on a higher layer parameter for each servingcell.

In step A2, m=0 is set. m may indicate an index of the monitoringoccasion for the PDCCH including DCI format 1_0 or DCI format 1_1.

In step A3, j may be set to 0.

In step A4, V_(temp) may be set to 0.

In step A5, V_(temp2) may be set to 0.

In step A6, V_(s)=φ may be set. φ indicates an empty set.

In step A7, N^(DL) _(cells) may be set to the number of serving cells.The number of serving cells may be the number of serving cellsconfigured for the terminal apparatus 1.

In step A8, M may be set to the number of monitoring occasions for thePDCCH.

In step A9, the first evaluation expression m<M is evaluated. In a casethat the first evaluation expression is true, step A10 may be performed.In a case that the first evaluation expression is false, step A34 may beperformed.

In step A10, c may be set to 0.

In step A11, the second evaluation expression c<N^(DL) _(cells) isevaluated. In a case that the second evaluation expression is true, stepAll may be performed. In a case that the second evaluation expression isfalse, step A33 may be performed.

In step A12, in a case that a monitoring occasion m for the PDCCH in aserving cell c is before switching of an activated downlink BWP, stepA13 may be performed. In step A12, in a case that there is switching ofan activated uplink BWP in the PCell, and switching of the activateddownlink BWP is not triggered by DCI format 1_1, step A13 may beperformed. In a case that neither of the two conditions described aboveis satisfied, step A14 may be performed.

In step A13, c may be set to c+1.

In step A14, step A15 may be performed.

In step A15, in a case that there is a PDSCH related to the PDCCH in themonitoring occasion m for the PDCCH in the serving cell c, or there is aPDCCH indicating release of the SPS PDSCH in the serving cell c, stepA16 may be performed.

In step A16, the third evaluation expression V^(DL)_(C-DAI, c, m)≤V_(temp) is evaluated. In a case that the thirdevaluation expression is true, step A17 may be performed. In a case thatthe third evaluation expression is false, step A18 may be performed.

V^(DL) _(C-DAI, c, m) is a value of a counter Downlink Assignment Index(DAI) given based at least on the PDCCH detected in the monitoringoccasion m for the PDCCH in the serving cell c. The counter DAIindicates a cumulative number of the PDCCHs detected before themonitoring occasion m for the PDCCH in the serving cell c (or may be avalue at least related to the cumulative number) in the M monitoringoccasions for the PDCCH. In determination of the cumulative number, forthe index of the PDCCH detected in the M monitoring occasions, theserving cell index c may be given first and the monitoring occasion mfor the PDCCH may be given second. In other words, the index of thePDCCH detected in the M monitoring occasions for the PDCCH is firstmapped in order of the serving cell index c, and may then be mapped inorder of the monitoring occasion m for the PDCCH (serving cell indexfirst, PDCCH monitoring occasion second mapping). The counter DAI may bereferred to as a Counter Downlink Assignment Index (C-DAI).

In step A17, j may be set to j+1.

Step A18 may be a step indicating completion of operation based on thethird evaluation expression in step A12.

In step A19, V_(temp) may be set to V^(DL) _(C-DAI, c, m).

In step A20, the fourth evaluation expression V^(DL) _(T-DAI, m)=φ maybe evaluated. In a case that the fourth evaluation expression is true,step A21 may be performed. In a case that the fourth evaluationexpression is false, step A22 may be performed.

V^(DL) _(T-DAI, m) may be a value of the total DAI given based at leaston the PDCCH detected in the monitoring occasion m for the PDCCH in theserving cell c. The total DAI may indicate a cumulative number of thePDCCHs detected before the monitoring occasion m for the PDCCH (or maybe a value at least related to the cumulative number) in the Mmonitoring occasions for the PDCCH. The total DAI may be referred to asa Total Downlink Assignment Index (T-DAI).

The codebook of the HARQ-ACK information may be multiplexed on the PUSCHscheduled based at least on DCI format 0_1, and V^(DL) _(T-DAI, m) maybe replaced by V^(UL) _(DAI) at least in a case that m=M−1.

In step A21, V_(temp2) may be set to V^(DL) _(C_DAI, c, m).

In step A22, step A23 may be performed.

In step A23, V_(temp2) may be set to V^(DL) _(T-DAI, m).

Step A24 may be a step indicating completion of operation based on thefourth evaluation expression in step A20.

In step A25, in a case that 1) harq-ACK-SpatialBundlingPUCCH is notprovided, 2) the monitoring occasion m for the PDCCH is a monitoringoccasion for the PDCCH including DCI format 1_0 or DCI format 1_1, 3)maxNrofCodeWordsScheduledByDCI is configured in at least one BWP in atleast one serving cell for reception of two transport blocks, step A26may be performed. maxNrofCodeWordsScheduledByDCI may be informationindicating whether or not transmission of two transport blocks on PDSCHis supported.

In step A26, o^(ACK) _(a)(8j+2 (V^(DL) _(C-DAI, c, m)−1)) may be set toa value of the HARQ-ACK bit corresponding to the first transport blockof the serving cell c. In a case that the value of the HARQ-ACK bit is1, this may indicate an ACK. In a case that the value of the HARQ-ACKbit is 0, this may indicate a NACK. The first transport block of theserving cell c may be the first transport block included in the PDSCHscheduled using a DCI format that is included in the PDCCH detected inthe monitoring occasion m for the PDCCH in the serving cell c.

In step A27, o^(ACK) _(a)(8j+2(V^(DL) _(C-DAI, c, m)−1)+1) may be set toa value of the HARQ-ACK bit corresponding to the second transport blockof the serving cell c. The second transport block of the serving cell cmay be the second transport block included in the PDSCH scheduled usinga DCI format that is included in the PDCCH detected in the monitoringoccasion m for the PDCCH in the serving cell c.

In a case that the PDSCH includes the first transport block, and thePDSCH does not include the second transport block, this may indicatethat one transport block is included in the PDSCH.

In step A28, V_(s) may be set to V_(s) ∪ {8j+2(V^(DL) _(C-DAI, c, m)−1),8j+2(V^(DL) _(C-DAI, c, m)−1)+1}. Y ∪ Z may indicate a union of set Yand set Z. {*} may be a set including*.

In step A29, in a case that 1) harq-ACK-SpatialBundlingPUCCH isprovided, 2) the monitoring occasion m for the PDCCH is a monitoringoccasion for the PDCCH including DCI format 1_1, and 3)maxNrofCodeWordsScheduledByDCI is configured in at least one BWP in atleast one serving cell for reception of two transport blocks, step A30may be performed.

In step A30, o^(ACK) _(a)(4j+V^(DL) _(C-DAI, c, m)−1) may be set to avalue given by a logical product (binary AND operation) of the firstHARQ-ACK bit corresponding to the first transport block of the servingcell c and the second HARQ-ACK bit corresponding to the second transportblock of the serving cell c.

In step A31, V_(s) may be set to V_(s) ∪ {4j+V^(DL) _(C-DAI, c, m)−1}.

In step A32, in a case that the condition of step A25 and the conditionof step A29 are not satisfied, step A33 may be performed.

In step A33, o^(ACK) _(a)(4j V^(DL) _(C-DAI, c, m) −1) may be set to avalue of the first HARQ-ACK bit corresponding to the first transportblock of the serving cell c. In step A33, O^(ACK) _(a)(4j+V^(DL)_(C-DAI, c, m)−1) may be set to a value of the HARQ-ACK bit of theserving cell c.

In step A34, V_(s) may be set to V_(s) ∪ {4j+V^(DL) _(C-DAI, c, m)1}.

Step A35 may be a step indicating completion of operation of step A25.

Step A36 may be a step indicating completion of operation of step A15.

In step A37, c may be set to c+1.

Step A38 may be a step indicating completion of operation of step A12.

In step A39, step A11 may be performed.

In step A40, m may be set to m+1.

In step A41, step A10 may be performed.

In step A42, the fifth evaluation expression V_(temp2)<V_(temp) may beperformed. In a case that the fifth evaluation expression is true, stepA43 may be performed. In a case that the fifth evaluation expression isfalse, step A44 may be performed.

In step A43, j may be set to j+1.

Step A44 may be a step indicating completion of step A42.

In step A45, in a case that 1) harq-ACK-SpatialBundlingPUCCH is notprovided, and 2) maxNrofCodeWordsScheduledByDCI is configured in atleast one BWP in at least one serving cell, step A46 may be performed.In a case that neither of the two conditions described above issatisfied, step A47 may be performed.

In step A46, O_(ACK) may be set to 2 (4j+V_(temp2)).

In step A47, step A48 may be performed.

In step A48, O_(ACK) may be set to 4j+V_(temp2).

Step A49 may be a step indicating completion of operation of step A12.

In step A50, o^(ACK) _(a)(i_(N)) may be set to a value of a NACK for iNthat satisfies i_(N) ∈{0, 1, . . . , O^(ACK)−1} ¥ V_(s). V ¥ W dicate aset obtained by eliminating elements included in set W from set V. ¥ Wmay be a set difference of V regarding W.

In step A51, c may be set to 0.

In step A52, the seventh evaluation expression c<N^(DL) _(cells) isevaluated. In a case that the seventh evaluation expression is true,step A54 may be performed. In a case that the second evaluationexpression is false, step A58 may be performed.

In step A54, in a case that a PDSCH (SPS PDSCH) scheduled using aconfigured grant in one or multiple slots in the M monitoring occasionsfor the PDCCH is configured to be received, and transmission of the SPSPDSCH is activated, step AM may be performed.

In step A54, O^(ACK) may be set to O^(ACK)+1. In step A44, O^(ACK) maybe set to O^(ACK)+N_(SPS). N_(SPS) may be the number of SPS PDSCHsconfigured to be received in M monitoring occasions 1001 for the PDCCH.

In step A55, o^(ACK) _(a)(o^(ACK) _(a)−1) may be set to a value of theHARQ-ACK bit corresponding to the transport block included in the SPSPDSCH. In step A45, o^(ACK) _(a)(o^(ACK) _(a)−i_(SPS)) may be set to avalue of the HARQ-ACK bit corresponding to the transport block includedin the SPS PDSCH. i_(SPS) may satisfy the condition of i_(sps) ∈ {0, 1,. . . , N_(SPS)−1}. In step A45, o^(ACK) _(a)(o^(ACK) _(a)−1) may be setto a value given by a logical product of the HARQ-ACK bits correspondingto the transport blocks included in each of one or multiple SPS PDSCHsconfigured to be received in M monitoring occasions for the PDCCH.

Step A56 may be a step indicating completion of operation of step A53.

In step A57, c may be set to c+1.

Step A58 may be a step indicating completion of operation of step A52.

The first evaluation expression to the seventh evaluation expression areeach also referred to as an evaluation expression. In a case that anevaluation expression is true, this may indicate that the evaluationexpression is satisfied. In a case that the evaluation expression isfalse, this may indicate that the evaluation expression is not true. Ina case that the evaluation expression is false, this may indicate thatthe evaluation expression is not satisfied.

The terminal apparatus 1 may be associated with a PDSCH Group ID (PGI)regarding each PDSCH. The PGI of a certain PDSCH may be indicated basedat least on a DCI format included in the PDCCH for scheduling the PDSCH.For example, a field indicating the PGI (PGI field) may be included inthe DCI format. The PDSCH group may be a set of PDSCHs having the samePGI (PDSCH group ID). The PDSCH group may be one PDSCH, or a set of oneor more PDSCHs associated with the same PGI.

For example, the PGI field may be included in DCI format 1_1. Forexample, the PGI field need not be included in DCI format 1_0. Forexample, the PGI field may be included in DCI format 1_0. For example,in a case that DCI format 1_0 not including the PGI field is detected,it may be considered that the PDSCH scheduled using DCI format 1_0 isincluded in a prescribed PDSCH group (for example, the PDSCH grouphaving an index of 0 or 1). For example, in a case that the terminalapparatus 1 detects DCI format 1_0 not including the PGI field, it maybe considered that the PDSCH scheduled using DCI format 1_0 is includedin a prescribed PDSCH group (for example, the PDSCH group having anindex of 0 or 1).

A Requested PDSCH Group (RPG) may be a PDSCH group corresponding to theHARQ-ACK feedback transmitted (reported) via the following PUCCH orPUSCH. The RPG (requested PDSCH group) may include one PDSCH group, ormay include multiple PDSCH groups. Indication of the RPG may beindicated in association with each PDSCH group in a format of a bitmap,based at least on the DCI format. The terminal apparatus 1 may generatethe HARQ-ACK codebook for the indicated RPG, and transmit (report) theHARQ-ACK codebook via the PUCCH or the PUSCH. The RPG may be indicatedbased at least on the RPG field included in the DCI format.

For example, the RPG field may be included in DCI format 1_1. Forexample, the RPG field need not be included in DCI format 1_0. Forexample, the RPG field may be included in DCI format 1_0. For example,in a case that DCI format 1_0 not including the RPG field is detected,it may be considered that transmission of the HARQ-ACK codebook for aprescribed PDSCH group (for example, the PDSCH group having an index of0 or 1) is triggered in transmission of the HARQ-ACK codebook triggeredusing DCI format 1_0. For example, in a case that the terminal apparatus1 detects DCI format 1_0 not including the RPG field, the terminalapparatus 1 may consider that transmission of the HARQ-ACK codebook fora prescribed PDSCH group (for example, the PDSCH group having an indexof 0 or 1) is triggered in transmission of the HARQ-ACK codebooktriggered using DCI format 1_0.

A value of K1 (information or a parameter indicated by the timingindication field from the PDSCH to the HARQ feedback) indicated by theDCI format included in the PDCCH may be a numerical value (numerical),or may be a non-numerical value (non-numerical). Here, the value of thenumerical value may indicate a value expressed in numbers, and forexample, may be a value out of {0, 1, 2, . . . , 151}. The value of thenon-numerical value indicates a value other than numbers. The use of thevalue of K1 being a numerical value and the value of K1 being anon-numerical value will be described below. For example, the PDSCHscheduled using the DCI format is transmitted in the base stationapparatus 3 in slot n, and is received in the terminal apparatus 1. In acase that the value of K1 indicated by the DCI format is a numericalvalue, the terminal apparatus 1 may transmit (report) the HARQ-ACKinformation corresponding to the PDSCH in slot n+K1 via the PUCCH or thePUSCH. In a case that the value of K1 indicated by the DCI format is anon-numerical value, the terminal apparatus 1 may defer reporting of theHARQ-ACK information corresponding to the PDSCH. In a case that thevalue of K1 being a non-numerical value is indicated by the DCI formatincluding scheduling information of the PDSCH, the terminal apparatus 1may defer reporting of the HARQ-ACK information corresponding to thePDSCH. For example, the terminal apparatus 1 may store the HARQ-ACKinformation, and transmit (report) the HARQ-ACK information with thetransmission of the HARQ-ACK information being triggered based at leaston a DCI format other than the DCI format described above, withouttransmitting (reporting) the HARQ-ACK information via the followingPUCCH or PUSCH.

A New Feedback Indicator (NFI) field may be a DCI field indicatingwhether or not the HARQ-ACK information of the PDSCH is correctlydetected. The NFI field may be included in DCI format 0_1. The NFI fieldmay be included in DCI format 1_0. The NFI field need not be included inDCI format 1_0. The NFI field may be 1 bit, or may be 1 bit or more.Each bit of the NFI field may correspond to each PDSCH group. Forexample, in a case that the number of PDSCH groups is two, the NFI fieldof 2 bits may be set with (X, Y), and NFI bit X may correspond to PDSCHgroup #1, and NFI bit Y may correspond to PDSCH group #2. For example,in a case that the number of PDSCH groups is 4, the NFI field of 4 bitsmay be set with (X, Y, Z, W), and NFI bit X may correspond to PDSCHgroup #1, NFI bit Y may correspond to PDSCH group #2, NFI bit Z maycorrespond to PDSCH group #3, and NFI bit W may correspond to PDSCHgroup #4.

For example, in a case that DCI format 1_0 not including the NFI fieldis detected, it may be considered that the NFI is toggled for the PDSCHgroup including the PDSCH scheduled using the DCI format. For example,in a case that DCI format 1_0 not including the NFI field is detected,it may be considered that the NFI is not toggled for the PDSCH groupincluding the PDSCH scheduled using the DCI format. For example, in acase that the terminal apparatus 1 detects DCI format 1_0 not includingthe NFI field, the terminal apparatus 1 may consider that the NFI istoggled for the PDSCH group including the PDSCH scheduled using the DCIformat. For example, in a case that the terminal apparatus 1 detects DCIformat 1_0 not including the NFI field, the terminal apparatus 1 mayconsider that the NFI is not toggled for the PDSCH group including thePDSCH scheduled using the DCI format.

After transmitting the first PUCCH or the first PUSCH, the terminalapparatus 1 may store a value of the NFI bit corresponding to each PDSCHgroup indicated by the PDCCH (or the DCI format) for scheduling thefirst PUCCH or the first PUSCH. In a case that the terminal apparatus 1receives the PDCCH (or the DCI format) for scheduling the first PUCCH orthe first PUSCH, the terminal apparatus 1 may store a value of the NFIbit corresponding to each PDSCH group indicated by the PDCCH (or the DCIformat). For each PDSCH group, the initial value of the stored value ofthe NFI bit may be set to 0 in advance. In a case that the terminalapparatus 1 transmits the second PUCCH or the second PUSCH subsequentlyto the first PUCCH or the first PUSCH, the terminal apparatus 1 maycompare a value of the NFI bit corresponding to the PDSCH groupindicated by the PDCCH for scheduling the second PUCCH or the secondPUSCH and the above-described stored value of the NFI bit for a certainPDSCH group. In other words, the terminal apparatus 1 may compare avalue of the received NFI bit and the value of the stored NFI bit andthereby determine whether or not the NFI bit corresponding to the PDSCHgroup is toggled. In a case that the two values of the NFI bits aredifferent, the terminal apparatus 1 may determine that the NFI bit istoggled, and the HARQ-ACK information corresponding to the PDSCH groupdescribed above is correctly detected. The terminal apparatus 1 maydetermine that the HARQ-ACK information corresponding to the PDSCH groupfor which the NFI bit is toggled is detected in the base stationapparatus 3. In a case that the base station apparatus 3 detects theHARQ-ACK information corresponding to the PDSCH group, the base stationapparatus 3 may toggle the NFI bit corresponding to the PDSCH group. Ina case that the two values of the NFI bits are the same, it may bedetermined that the NFI bit is not toggled, and the HARQ-ACK informationcorresponding to the PDSCH group described above is not correctlydetected. The terminal apparatus 1 may determine that the HARQ-ACKinformation corresponding to the PDSCH group for which the NFI bit isnot toggled is not detected in the base station apparatus 3. In a casethat the base station apparatus 3 does not detect the HARQ-ACKinformation corresponding to the PDSCH group, the base station apparatus3 need not toggle the NFI bit corresponding to the PDSCH group. Here,“to toggle” means to switch to a different value.

In a case that the terminal apparatus 1 generates the HARQ-ACK codebookcorresponding to a certain PDSCH group, and the NFI bit corresponding tothe PDSCH group is toggled, the terminal apparatus 1 may delete (neednot include) the HARQ-ACK information already reported (HARQ-ACKinformation other than HARQ-ACK information not reported yet) from theHARQ-ACK codebook corresponding to the PDSCH group. In a case that thereis a PDSCH that is detected and for which the HARQ-ACK information isnot reported yet out of the PDSCH group, the terminal apparatus 1 neednot delete (may include) the HARQ-ACK information corresponding to thePDSCH. In other words, the terminal apparatus 1 may multiplex theHARQ-ACK information corresponding to the PDSCH on the HARQ-ACK codebookdescribed above. For one or more pieces of HARQ-ACK informationcorresponding to the PDSCH group for which the NFI bit is toggled, theterminal apparatus 1 may flush the HARQ-ACK information that is alreadyreported, and need not flush the HARQ-ACK information that is notreported. Here, “to flush” means to bring the HARQ-ACK information tothe initial value (for example, a NACK). In a case that the terminalapparatus 1 receives the NFI being toggled and then transmits theHARQ-ACK codebook corresponding to the PDSCH group for the NFI bit, theterminal apparatus 1 generates the HARQ-ACK codebook by using theHARQ-ACK information not being flushed (HARQ-ACK information not beingreported) and transmits the HARQ-ACK codebook. In a case that theterminal apparatus 1 receives the NFI not being toggled and thentransmits the HARQ-ACK codebook corresponding to the PDSCH group for theNFI bit, the terminal apparatus 1 generates the HARQ-ACK codebook byusing the HARQ-ACK information not being flushed (HARQ-ACK informationbeing reported and HARQ-ACK information not being reported) andtransmits the HARQ-ACK codebook.

FIG. 11 is a diagram illustrating an example of reporting of theHARQ-ACK information according to an aspect of the present embodiment.

With a DCI format of a PDCCH 1101 for scheduling a PDSCH 1111, G1 isindicated as a PDSCH group ID (PGI), and a numerical value is indicatedby a K1. With a DCI format of a PDCCH 1102 for scheduling a PDSCH 1112,G2 is indicated as the PGI, a first value is indicated as the NFIcorresponding to the PDSCH group G2, and a non-numerical value isindicated as K1. With a DCI format of a PDCCH 1103 for scheduling aPDSCH 1113, G1 is indicated as the PGI, and a numerical value isindicated as K1. With a DCI format of a PDCCH 1104 for scheduling aPDSCH 1114, G2 is indicated as the PGI, a second value is indicated asthe NFI corresponding to the PDSCH group G2, and a non-numerical valueindicated as K1. With a DCI format of a PDCCH 1105 for scheduling aPDSCH 1115, a third value is indicated as the NFI corresponding to thePDSCH group G2. A HARQ-ACK codebook 1131 is transmitted (reported) via aPUCCH 1123. The HARQ-ACK codebook 1131 corresponds to the PDSCH group G1and/or the PDSCH group G2. The HARQ-ACK codebook 1131 may correspond tothe requested PDSCH group (RPG) indicated based at least on the DCIformat of the PDCCH 1105.

In FIG. 11 , the terminal apparatus 1 may multiplex the HARQ-ACKinformation corresponding to the PDSCH 1112 on the HARQ-ACK codebooktransmitted via a PUCCH 1122, regardless of whether or not the firstvalue and the second value are different (in other words, whether or notthe NFI is toggled) (whether or not the NFI corresponding to the PDSCHgroup G2 is toggled). The terminal apparatus 1 may multiplex theHARQ-ACK information corresponding to the PDSCH 1114 on the HARQ-ACKcodebook 1131 transmitted via the PUCCH 1123, regardless of whether ornot the second value and the third value are different (whether or notthe NFI corresponding to the PDSCH group G2 is toggled). In a case thatthe second value and the third value are the same (in other words, nottoggled) (NFI corresponding to the PDSCH group G2 is not toggled), theterminal apparatus 1 may multiplex the HARQ-ACK informationcorresponding to the PDSCH 1112 on the HARQ-ACK codebook 1131, andretransmits the HARQ-ACK information of the PDSCH 1112. In a case thatthe second value and the third value are different (in other words,toggled) (NFI corresponding to the PDSCH group G2 is toggled), theterminal apparatus 1 need not retransmit the HARQ-ACK information of thePDSCH 1112.

FIG. 12 is an example illustrating a toggle state of the NFI bitaccording to an aspect of the present embodiment.

A received NFI may be an NFI indicated by the PDCCH (or, the DCI format)for scheduling the PDSCH. A stored NFI may be an NFI already stored inthe terminal apparatus 1 before the PDCCH for scheduling the PDSCH isdetected. Each entry of the stored NFI may be a stored NFI bitcorresponding to each of the PDSCH groups (for example, the PDSCH groupG1 and the PDSCH group G2). For example, in a case that the stored NFIis (0, 1), the value of the stored NFI bit of the PDSCH group G1 is 0,and the value of the stored NFI bit of the PDSCH group G2 is 1. In thetable of FIG. 12 , for the PDSCH group G2, the concept of the stored NFIbit and the received NFI bit will be described using the specificexample of FIG. 11 . At the time point that the terminal apparatus 1detects the PDCCH 1101, the value of the stored NFI bit is the initialvalue, and the received NFI bit is not indicated by the PDCCH 1101.After the PDCCH 1101 is detected, the value of the stored NFI bit neednot be updated. At the time point that the terminal apparatus 1 detectsthe PDCCH 1102, the value of the stored NFI bit is the initial value,and the value of the received NFI bit is the first value indicated bythe PDCCH 1102. After the PDCCH 1102 is detected, the value of thestored NFI bit may be updated to the first value. At the time point thatthe terminal apparatus 1 detects the PDCCH 1103, the value of the storedNFI bit is the first value, and the received NFI bit is not indicated bythe PDCCH 1103. After the PDCCH 1103 is detected, the value of thestored NFI bit need not be updated. At the time point that the terminalapparatus 1 detects the PDCCH 1104, the value of the stored NFI bit isthe first value, and the value of the received NFI bit is the secondvalue indicated by the PDCCH 1104. After the PDCCH 1104 is detected, thevalue of the stored NFI bit may be updated to the second value. At thetime point that the terminal apparatus 1 detects the PDCCH 1105, thevalue of the stored NFI bit is the second value, and the value of thereceived NFI bit is the third value indicated by the PDCCH 1105. Inother words, in a certain case, in a case that the PGI indicated by theDCI format for scheduling the PDSCH is G1, the terminal apparatus 1 neednot update the received NFI corresponding to the PDSCH group G2. In acertain case, in a case that the PGI indicated by the DCI format forscheduling the PDSCH is G1, the terminal apparatus 1 need not update thestored NFI corresponding to the PDSCH group G2. In a certain case, in acase that the PGI indicated by the DCI format for scheduling the PDSCHis G1, the terminal apparatus 1 need not update the received NFIcorresponding to the PDSCH group G2; however, the terminal apparatus 1may update the stored NFI for the PDSCH group G2.

The terminal apparatus 1 may process the HARQ-ACK information, dependingon a report state of the HARQ-ACK information corresponding to thePDSCH, and whether or not the NFI bit of the PDSCH group to which thePDSCH belongs is toggled. In a case that, for a certain PDSCH, thereport state of the HARQ-ACK information corresponding to the PDSCH isalready reported, and the NFI bit corresponding to the PDSCH group towhich the PDSCH belongs is toggled, the terminal apparatus 1 maydetermine that the HARQ-ACK information corresponding to the PDSCH iscorrectly detected. In other words, in a case that the NFI bitcorresponding to the PDSCH group to which the PDSCH belongs is toggled,the terminal apparatus 1 need not perform retransmission of the HARQ-ACKinformation. In a case that the terminal apparatus 1 toggles the NFI bitcorresponding to the PDSCH group to which the PDSCH belongs, theHARQ-ACK information may be deleted. In other words, in a case that theterminal apparatus 1 generates the HARQ-ACK codebook after determiningdeletion of the HARQ-ACK information, the terminal apparatus 1 need nottake the HARQ-ACK information into consideration. The HARQ-ACKinformation corresponding to a certain PDSCH may be referred to as anHARQ-ACK entry of the PDSCH in the HARQ-ACK codebook. The HARQ-ACK entrymay include one HARQ-ACK bit, or may include multiple HARQ-ACK bits.

In a case that, for a certain PDSCH, the report state of the HARQ-ACKinformation corresponding to the PDSCH is not-reported, and the NFI bitcorresponding to the PDSCH group to which the PDSCH belongs is toggled,the terminal apparatus 1 need not determine that the HARQ-ACKinformation corresponding to the PDSCH is correctly detected. In otherwords, in a case that the NFI bit corresponding to the PDSCH group towhich the PDSCH belongs is toggled, the terminal apparatus 1 may performtransmission of the HARQ-ACK information. In a case that the NFI bitcorresponding to the PDSCH group to which the PDSCH belongs is toggled,the terminal apparatus 1 need not delete the HARQ-ACK information. Inother words, in a case that the terminal apparatus 1 generates theHARQ-ACK codebook, the terminal apparatus 1 may take the HARQ-ACKinformation into consideration.

In FIG. 11 , in a case that the NFI bit corresponding to the PDSCH groupG2 is not toggled in a case that the terminal apparatus 1 generates theHARQ-ACK codebook (for example, the HARQ-ACK codebook 1131) transmittedon the PUCCH (for example, the PUCCH 1123), the terminal apparatus 1 maygenerate the HARQ-ACK codebook 1131 so as to include both of theHARQ-ACK information corresponding to the PDSCH that is already reported(for example, the HARQ-ACK information corresponding to the PDSCH 1112)and the HARQ-ACK information corresponding to the PDSCH that is notreported yet (for example, the HARQ-ACK information corresponding to thePDSCH 1114). Here, the HARQ-ACK information corresponding to the PDSCHnot reported may include the HARQ-ACK information corresponding to thePDSCH scheduled by the PDCCH with the HARQ-ACK feedback timingindicating the value of K1 being a slot of its PUCCH (for example,HARQ-ACK information corresponding to the PDSCH 1115). Alternatively,the HARQ-ACK information corresponding to the PDSCH not reported neednot include the HARQ-ACK information corresponding to the PDSCHscheduled by the PDCCH including its NFI (for example, HARQ-ACKinformation corresponding to the PDSCH 1115). In this case, in a casethat the NFI bit corresponding to the PDSCH group G2 is not toggled, theHARQ-ACK codebook 1131 may be generated so as to include all of theHARQ-ACK information corresponding to the PDSCH that is already reported(for example, HARQ-ACK information corresponding to the PDSCH 1112), theHARQ-ACK information corresponding to the PDSCH that is not reported yet(for example, HARQ-ACK information corresponding to the PDSCH 1114), andthe HARQ-ACK information corresponding to the PDSCH scheduled by thePDCCH with the HARQ-ACK feedback timing indicating the value of K1 beinga slot of its PUCCH (for example, HARQ-ACK information corresponding tothe PDSCH 1115). In FIG. 11 , in a case that the NFI bit correspondingto the PDSCH group G2 is toggled in a case that the terminal apparatus 1generates the HARQ-ACK codebook 1131, the terminal apparatus 1 maydelete (need not include) the HARQ-ACK information corresponding to thePDSCH 1112. In other words, the terminal apparatus 1 need not multiplexthe HARQ-ACK information corresponding to the PDSCH 1112 on the HARQ-ACKcodebook 1131. The terminal apparatus 1 may multiplex the HARQ-ACKinformation corresponding to the PDSCH 1114 on the HARQ-ACK codebook1131. Here, whether or not the NFI bit is toggled may be determinedbased at least on comparison between the value of the NFI bit indicatedby the PDCCH 1105 and the value of the NFI bit indicated by the PDCCH1103. In a case that the two values are different, the terminalapparatus 1 may determine that the NFI bit is toggled, and in a casethat the two values are the same, the terminal apparatus 1 may determinethat the NFI bit is not toggled. Note that, to multiplex the HARQ-ACKinformation on the HARQ-ACK codebook may mean that the HARQ-ACK codebookincludes the HARQ-ACK information in a case of generating the HARQ-ACKcodebook. Alternatively, it may mean that the HARQ-ACK information andthe HARQ-ACK codebook are multiplexed on the same signal or channel

FIG. 13 is an example of reporting of the HARQ-ACK information in a casethat the NFI bit corresponding to a certain PDSCH group is toggledaccording to an aspect of the present embodiment.

In FIG. 11 and FIG. 13 , with the example of generation of the HARQ-ACKcodebook 1131, relation to the HARQ-ACK feedback will be described. TheHARQ-ACK feedback refers to a process that the terminal apparatus 1transmits, to the base station apparatus 3, the HARQ-ACK correspondingto the transport block included in the received PDSCH.

In FIG. 13 , based on the table of FIG. 12 , indication from the basestation apparatus 3 and processing in the terminal apparatus 1 relatedto generation of the HARQ-ACK codebook will be described. The basestation apparatus 3 indicates G1 as the PGI, G1 as the RPG, 1 as theC-DAI, and (0, 0) as the NFI via the PDCCH 1101. In a case that the NFIis not indicated (received) before the PDSCH 1111 is detected, theterminal apparatus 1 keeps the stored NFI at the initial value of (0,0). The terminal apparatus 1 detects the PDCCH 1101, and recognizes thatthe PGI of the PDSCH 1111 scheduled by the PDCCH 1101 is G1, the RPG isG1, the C-DAI is 1, and the received NFI is (0, 0). By comparing thereceived NFI bit for the PDSCH group G1 and the stored NFI bit for thePDSCH group G1, the terminal apparatus 1 may determine that the NFI bitof the PDSCH group G1 is not toggled. By comparing the received NFI forthe PDSCH group G2 and the stored NFI for the PDSCH group G2, theterminal apparatus 1 may determine that the NFI bit of the PDSCH groupG2 is not toggled. The terminal apparatus 1 may set the report state ofthe HARQ-ACK information corresponding to the PDSCH 1111 tonot-reported. Here, in the terminal apparatus 1, in a case that theHARQ-ACK information corresponding to the PDSCH is not already reported,the report state may be set to already reported, and in a case that theabove-described HARQ-ACK information is not reported, the report statemay be set to not-reported. In the terminal apparatus 1, in a case thattransmission of the HARQ-ACK information corresponding to the PDSCH in acertain uplink physical channel is already triggered, and transmissionof the resource of the uplink physical channel is attempted, the reportstate may be set to already reported, and in a case that transmission ofthe above-described HARQ-ACK information in a certain uplink physicalchannel is already triggered, and transmission of the resource of theuplink physical channel is not attempted, the report state may be set tonot-reported. In transmission of the HARQ-ACK information correspondingto the PDSCH in a certain uplink physical channel is not triggered inthe terminal apparatus 1, the report state may be set to not-reported orN/A. The initial value of the report state may be set to N/A in advance.

In FIG. 13 , the terminal apparatus 1 detects the PDCCH 1102, andrecognizes that the PGI of the PDSCH 1112 scheduled by the PDCCH 1102 isG2, the C-DAI is 1, and the received NFI is (0, 0). The terminalapparatus 1 may ignore the RPG indicated by the PDCCH (for example, thePDCCH 1102 and the PDCCH 1104) having K1 being a non-numerical value. Inother words, the requested PDSCH group may be determined based at leaston the PDCCH (for example, the PDCCH having K1 being a numerical value)other than the PDCCH having K1 being a non-numerical value. For example,the requested PDSCH group corresponding to the HARQ-ACK codebookincluding the HARQ-ACK information transmitted on a certain PUCCH may beindicated by the RPG field included in the DCI format used fordetermination of the resource of the certain PUCCH. By updating thestored NFI to the NFI (specifically, (0, 0)) indicated by the PDCCH 1101and comparing the received NFI (specifically, (0, 0)) and the stored NFI(specifically, (0, 0)), the terminal apparatus 1 may determine that theNFI bit corresponding to each of the PDSCH group G1 and the PDSCH groupG2 is not toggled. The terminal apparatus 1 may set the report state ofthe HARQ-ACK information corresponding to the PDSCH 1112 tonot-reported. The terminal apparatus 1 may include the HARQ-ACKinformation corresponding to the PDSCH (for example, the PDSCH 1111) atleast satisfying a part or all of condition A1 to condition A4 in theHARQ-ACK codebook, and transmit (report) the HARQ-ACK information via aPUCCH 1121.

Condition A1: The PGI is included in the requested PDSCH group

Condition A2: The report state of the HARQ-ACK information isnot-reported

Condition A3: The HARQ-ACK information whose associated value of K1 is anumerical value or associated value of K1 is a non-numerical value isdeferred

Condition A4: Regarding the PDSCH group including the PDSCHcorresponding to the HARQ-ACK information, the NFI is toggled

For example, a state in which the report state of the HARQ-ACKinformation is not-reported may be a state that transmission of theHARQ-ACK information is not triggered. For example, a state in which thereport state of the HARQ-ACK information is not-reported may be a statein which new transmission of the HARQ-ACK information is not triggered.For example, a state in which the report state of the HARQ-ACKinformation is not-reported may be a state in which transmission of theHARQ-ACK information has been triggered. For example, a state in whichthe report state of the HARQ-ACK information is not-reported may be astate in which new transmission of the HARQ-ACK information is alreadytriggered. For example, a state in which the report state of theHARQ-ACK information is not-reported may be a state in which the reportstate of the HARQ-ACK information is already reported.

In FIG. 13 , at the time point that the HARQ-ACK codebook transmitted(reported) via the PUCCH 1122 is generated, the HARQ-ACK informationcorresponding to the PDSCH 1112 having K1 being a non-numerical valuehas already been deferred (has been postponed), and the HARQ-ACKinformation corresponding to the PDSCH 1114 having K1 being anon-numerical value is to be deferred (to be postponed). In a case thatthe terminal apparatus 1 generates the above-described HARQ-ACKcodebook, the terminal apparatus 1 need not multiplex the HARQ-ACKinformation to be deferred (for example, the HARQ-ACK informationcorresponding to the PDSCH 114) on the HARQ-ACK codebook.

In FIG. 13 , it is assumed that the base station apparatus 3 correctlydetects the HARQ-ACK codebook transmitted (reported) via the PUCCH 1121.The terminal apparatus 1 detects the PDCCH 1103, and recognizes that thePGI of the PDSCH 1113 scheduled by the PDCCH 1103 is G1, the RPG is G1and G2, the C-DAI is 1, and the received NFI is (1, 0). The terminalapparatus 1 updates the stored NFI to the NFI (specifically, (0, 0))indicated by the PDCCH 1102. By comparing the received NFI bit for thePDSCH group G1 and the stored NFI bit for the PDSCH group G1, theterminal apparatus 1 may determine that the NFI bit of the PDSCH groupG1 is toggled. By comparing the received NFI bit for the PDSCH group G2and stored NFI bit for the PDSCH group G2, the terminal apparatus 1 maydetermine that the NFI bit of the PDSCH group G2 is not toggled. Theterminal apparatus 1 may update the report state of the HARQ-ACKinformation corresponding to the PDSCH 1111 to already reported(reported), or may set the report state of the HARQ-ACK informationcorresponding to the PDSCH 1113 to not-reported.

The terminal apparatus 1 detects the PDCCH 1104, and recognizes that thePGI of the PDSCH 1114 scheduled by the PDCCH 1104 is G2, the C-DAI is 2,and the received NFI is (1, 0). The terminal apparatus 1 updates thestored NFI to the NFI (specifically, (1, 0)) indicated by the PDCCH1103. By comparing the received NFI bit for the PDSCH group G1 and thestored NFI bit for the PDSCH group G1, the terminal apparatus 1 maydetermine that the NFI bit of the PDSCH group G1 is not toggled. Bycomparing the received NFI bit for the PDSCH group G2 and stored NFI bitfor the PDSCH group G2, the terminal apparatus 1 may determine that theNFI bit of the PDSCH group G2 is not toggled. The terminal apparatus 1may reset the report state of the HARQ-ACK information corresponding tothe PDSCH 1111 to the initial value (for example, N/A), or may set thereport state of the HARQ-ACK information corresponding to the PDSCH 1114to not-reported. Here, the terminal apparatus 1 may flush the HARQ-ACKinformation, based at least on a fact that the NFI bit corresponding tothe PDSCH group G1 is toggled, and the report state of the HARQ-ACKinformation corresponding to the PDSCH 1111 is already reported. Theterminal apparatus 1 need not flush the HARQ-ACK information based atleast on a fact that the NFI bit corresponding to the PDSCH group G2 isnot toggled, and/or the report state of the HARQ-ACK informationcorresponding to the PDSCH 1112 is not-reported. The terminal apparatus1 may multiplex the HARQ-ACK information corresponding to the PDSCH (inother words, the PDSCH 1112 and the PDSCH 1113) at least satisfying apart or all of condition A1 to condition A4 on the HARQ-ACK codebook,and transmit (report) the HARQ-ACK information via the PUCCH 1122.

In FIG. 13 , it is assumed that the base station apparatus 3 correctlydetects the HARQ-ACK codebook transmitted (reported) via the PUCCH 1122.The terminal apparatus 1 detects the PDCCH 1105, and recognizes that thePGI of the PDSCH 1115 scheduled by the PDCCH 1105 is G1, the RPG is G1and G2, the C-DAI is 1, and the received NFI is (0, 1). The terminalapparatus 1 updates the stored NFI to the NFI (specifically, (1, 0))indicated by the PDCCH 1104. By comparing the received NFI bit for thePDSCH group G1 and the stored NFI bit for the PDSCH group G1, theterminal apparatus 1 may determine that the NFI bit of the PDSCH groupG1 is toggled. By comparing the received NFI bit for the PDSCH group G2and stored NFI bit for the PDSCH group G2, the terminal apparatus 1 maydetermine that the NFI bit of the PDSCH group G2 is toggled. Here, theterminal apparatus 1 may flush the HARQ-ACK information, based at leaston a fact that the NFI bit corresponding to the PDSCH group G1 istoggled, and the report state of the HARQ-ACK information correspondingto the PDSCH 1113 is already reported. The terminal apparatus 1 mayflush the HARQ-ACK information, based at least on a fact that the NFIbit corresponding to the PDSCH group G2 is toggled, and the report stateof the HARQ-ACK information corresponding to the PDSCH 1112 is alreadyreported. The terminal apparatus 1 need not flush the HARQ-ACKinformation, based at least on a fact that the NFI bit corresponding tothe PDSCH group G2 is toggled, and/or the report state of the HARQ-ACKinformation corresponding to the PDSCH 1114 is not-reported. Theterminal apparatus 1 may update the report state of the HARQ-ACKinformation corresponding to the PDSCH 1112 to already reported, mayupdate the report state of the HARQ-ACK information corresponding to thePDSCH 1113 to already reported, and may set the report state of theHARQ-ACK information corresponding to the PDSCH 1115 to not-reported.The terminal apparatus 1 may multiplex the HARQ-ACK informationcorresponding to the PDSCH (for example, the PDSCH 1114 and the PDSCH1115) at least satisfying a part or all of condition A1 to condition A4on the HARQ-ACK codebook 1131, and transmit (report) the HARQ-ACKinformation via the PUCCH 1123.

FIG. 14 is an example of reporting of the HARQ-ACK information in a casethat the NFI bit corresponding to a certain PDSCH group is not toggledaccording to an aspect of the present embodiment.

In FIG. 14 , the base station apparatus 3 assumes that the base stationapparatus 3 does not detect the PUCCH 1122. In other words, a scenarioin which the terminal apparatus 1 retransmits the HARQ-ACK informationincluded in the PUCCH 1122 is assumed. The terminal apparatus 1 detectsthe PDCCH 1105, and recognizes that the PGI of the PDSCH 1115 scheduledby the PDCCH 1105 is G1, the RPG is G1 and G2, the C-DAI is 2, and thereceived NFI is (1, 0). The terminal apparatus 1 updates the stored NFIto the NFI (specifically, (1, 0)) indicated by the PDCCH 1104. Bycomparing the received NFI bit for the PDSCH group G1 and the stored NFIbit for the PDSCH group G1, the terminal apparatus 1 may determine thatthe NFI bit of the PDSCH group G1 is not toggled. By comparing thereceived NFI bit for the PDSCH group G2 and stored NFI bit for the PDSCHgroup G2, the terminal apparatus 1 may determine that the NFI bit of thePDSCH group G2 is not toggled. The terminal apparatus 1 may set thereport state of the HARQ-ACK information corresponding to the PDSCH 1115to not-reported. Here, the terminal apparatus 1 need not flush theHARQ-ACK information, based at least on a fact that the NFI bitcorresponding to the PDSCH group G1 is not toggled, and/or the reportstate of the HARQ-ACK information corresponding to the PDSCH 1113 isalready reported. The terminal apparatus 1 need not flush the HARQ-ACKinformation, based at least on a fact that the NFI bit corresponding tothe PDSCH group G2 is not toggled, and/or the report state of theHARQ-ACK information corresponding to the PDSCH 1112 is alreadyreported. The terminal apparatus 1 need not flush the HARQ-ACKinformation, based at least on a fact that the NFI bit corresponding tothe PDSCH group G2 is not toggled, and/or the report state of theHARQ-ACK information corresponding to the PDSCH 1114 is not-reported.The terminal apparatus 1 may multiplex, on the HARQ-ACK codebook 1131,the HARQ-ACK information corresponding to the PDSCH (for example, thePDSCH 1112, the PDSCH 1113, the PDSCH 1114, and the PDSCH 1115) at leastsatisfying a part or all of condition A1 to condition A4, and transmit(report) the HARQ-ACK information via the PUCCH 1123. Here, transmissionof the HARQ-ACK information corresponding to the PDSCH 1112 and thePDSCH 1113 is retransmission, and transmission of the HARQ-ACKinformation corresponding to the PDSCH 1114 and the PDSCH 1115 is theinitial transmission.

Various aspects of apparatuses according to an aspect of the presentembodiment will be described below.

(1) In order to achieve the aforementioned object, aspects of thepresent invention provide the following measures. Specifically, a firstaspect of the present invention is a terminal apparatus including: areceiver configured to receive a PDCCH and receive a PDSCH scheduled bythe PDCCH; and a transmitter configured to transmit (report), via aPUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH,wherein PDCCH #C, PDCCH #G, and PDCCH #I are received, PDSCH #C isscheduled by the PDCCH #C, PDSCH #G is scheduled by the PDCCH #G, andPDSCH #I is scheduled by the PDCCH #I, the PDCCH #G indicates a secondvalue, and the PDCCH #I indicates a third value, the PDCCH #I indicatestransmission of at least HARQ-ACK information #I corresponding to thePDSCH #I on PUCCH #3, in a case that the second value and the thirdvalue are different from each other, HARQ-ACK information #Gcorresponding to the PDSCH #G and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, in a case that the second value is equal tothe third value, HARQ-ACK information #C corresponding to the PDSCH #C,the HARQ-ACK information #G, and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, the HARQ-ACK information #G is newtransmission on the PUCCH #3, and the HARQ-ACK information #C isretransmission on the PUCCH #3.

(2) A second aspect of the present invention is a terminal apparatusincluding: a receiver configured to receive a PDCCH and receive a PDSCHscheduled by the PDCCH; and a transmitter configured to transmit(report), via a PUCCH or a PUSCH, HARQ-ACK information corresponding tothe PDSCH, wherein based at least on the PDCCH, a PDSCH group ID and atoggle bit corresponding to the PDSCH group ID are indicated, in a casethat the toggle bit is toggled, HARQ-ACK information being alreadyreported (the HARQ-ACK information other than HARQ-ACK information notbeing reported yet) is deleted from an HARQ-ACK codebook correspondingto the PDSCH group ID, and the HARQ-ACK information corresponding to thePDSCH scheduled by the PDCCH is included in the HARQ-ACK codebook.

(3) A third aspect of the present invention is a base station apparatusincluding: a transmitter configured to transmit a PDCCH and transmit aPDSCH scheduled by the PDCCH; and a receiver configured to receive, viaa PUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH,wherein PDCCH #C, PDCCH #G, and PDCCH #I are transmitted, PDSCH #C isscheduled by the PDCCH #C, PDSCH #G is scheduled by the PDCCH #G, andPDSCH #I is scheduled by the PDCCH #I, the PDCCH #G indicates a secondvalue, and the PDCCH #I indicates a third value, the PDCCH #I indicatestransmission of at least HARQ-ACK information #I corresponding to thePDSCH #I on PUCCH #3, in a case that the second value and the thirdvalue are different from each other, HARQ-ACK information #Gcorresponding to the PDSCH #G and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, in a case that the second value is equal tothe third value, HARQ-ACK information #C corresponding to the PDSCH #C,the HARQ-ACK information #G, and the HARQ-ACK information #I aremultiplexed on the PUCCH #3, the HARQ-ACK information #G is newtransmission on the PUCCH #3, and the HARQ-ACK information #C isretransmission on the PUCCH #3.

(4) A fourth aspect of the present invention is a base station apparatusincluding: a transmitter configured to transmit a PDCCH and transmit aPDSCH scheduled by the PDCCH; and a receiver configured to receive, viaa PUCCH or a PUSCH, HARQ-ACK information corresponding to the PDSCH,wherein based at least on the PDCCH, a PDSCH group ID and a toggle bitcorresponding to the PDSCH group ID are indicated, in a case that thetoggle bit is toggled, HARQ-ACK information being already reported (theHARQ-ACK information other than HARQ-ACK information not being reportedyet) is deleted from an HARQ-ACK codebook corresponding to the PDSCHgroup ID, and the HARQ-ACK information corresponding to the PDSCHscheduled by the PDCCH is included in the HARQ-ACK codebook.

According to the above-described embodiment related to an aspect of thepresent invention, transmission and/or reception of the HARQ-ACKinformation between the terminal apparatus 1 and the base stationapparatus 3 can be appropriately implemented. By performing appropriatecontrol so that the HARQ-ACK information that is not detected in thebase station apparatus 3 is retransmitted by the terminal apparatus 1,and by performing appropriate control so that the HARQ-ACK informationthat is detected in the base station apparatus 3 is not retransmitted bythe terminal apparatus 1, an aspect of the present invention enablesimplementation of efficient communication.

A program running on the base station apparatus 3 and the terminalapparatus 1 according to one aspect of the present invention may be aprogram (program that causes a computer to function) that controls aCentral Processing Unit (CPU) and the like, such that the programrealizes the functions of the above-described embodiment according toone aspect of the present invention. Also, the information handled inthese apparatuses is temporarily loaded into a Random Access Memory(RAM) while being processed, is then stored in a Hard Disk Drive (HDD)and various types of Read Only Memory (ROM) such as a Flash ROM, and isread, modified, and written by the CPU, as necessary.

Note that the terminal apparatus 1 and the base station apparatus 3according to the aforementioned embodiment may be partially implementedby a computer. In such a case, a program for implementing such controlfunctions may be recorded on a computer-readable recording medium tocause a computer system to read and execute the program recorded on thisrecording medium.

Note that it is assumed that the “computer system” mentioned here refersto a computer system built into the terminal apparatus 1 or the basestation apparatus 3, and the computer system includes an OS and hardwarecomponents such as a peripheral device. Furthermore, a“computer-readable recording medium” refers to a portable medium such asa flexible disk, a magneto-optical disk, a ROM, a CD-ROM, and the like,and a storage device such as a hard disk built into the computer system.

Moreover, the “computer-readable recording medium” may include a mediumthat dynamically retains the program for a short period of time, such asa communication wire that is used to transmit the program over a networksuch as the Internet or over a communication line such as a telephoneline, and a medium that retains the program for a certain period oftime, such as a volatile memory within the computer system whichfunctions as a server or a client in a case that the program istransmitted via the communication wire. Furthermore, the aforementionedprogram may be configured to implement part of the functions describedabove, and also may be configured to be capable of implementing thefunctions described above in combination with a program already recordedin the computer system.

The terminal apparatus 1 may include at least one processor, and atleast one memory including a computer program instruction (computerprogram). The memory and the computer program instruction (computerprogram) may adopt a configuration of causing the terminal apparatus 1to perform the operation and the processing described in the aboveembodiment by using a processor. The base station apparatus 3 mayinclude at least one processor, and at least one memory including acomputer program instruction (computer program). The memory and thecomputer program instruction (computer program) may adopt aconfiguration of causing the base station apparatus 3 to perform theoperation and the processing described in the above embodiment by usinga processor.

Furthermore, the base station apparatus 3 according to theaforementioned embodiment may be achieved as an aggregation (apparatusgroup) including multiple apparatuses. Each of the apparatuses includedin such an apparatus group may include each function, or some or allportions of each functional block of the base station apparatus 3according to the aforementioned embodiment. As the apparatus group, itis only necessary to have a complete set of functions or functionalblocks of the base station apparatus 3. Moreover, the terminal apparatus1 according to the aforementioned embodiment can also communicate withthe base station apparatus as the aggregation.

Also, the base station apparatus 3 according to the aforementionedembodiment may be an Evolved Universal Terrestrial Radio Access Network(EUTRAN) and/or a NextGen RAN (NG-RAN or NR RAN). Moreover, the basestation apparatus 3 according to the aforementioned embodiment may havesome or all of the functions of a higher node for an eNodeB and/or agNB.

Also, some or all portions of each of the terminal apparatus 1 and thebase station apparatus 3 according to the aforementioned embodiment maybe implemented as an LSI which is a typical integrated circuit or may beimplemented as a chip set. The functional blocks of each of the terminalapparatus 1 and the base station apparatus 3 may be individuallyimplemented as a chip, or some or all of the functional blocks may beintegrated into a chip. A circuit integration technique is not limitedto the LSI, and may be implemented with a dedicated circuit or ageneral-purpose processor. Moreover, in a case that with advances insemiconductor technology, a circuit integration technology with which anLSI is replaced appears, it is also possible to use an integratedcircuit based on the technology.

In addition, although the aforementioned embodiments have described theterminal apparatus as an example of a communication apparatus, thepresent invention is not limited to such a terminal apparatus, and isapplicable to a terminal apparatus or a communication apparatus that isa stationary type or a non-movable type electronic apparatus installedindoors or outdoors, for example, such as an AV device, a kitchendevice, a cleaning or washing machine, an air-conditioning device,office equipment, a vending machine, and other household appliances.

Although, the embodiments of the present invention have been describedin detail above referring to the drawings, the specific configuration isnot limited to the embodiments and includes, for example, design changeswithin the scope not depart from the gist of the present invention.Furthermore, various modifications are possible within the scope of oneaspect of the present invention defined by claims, and embodiments thatare made by suitably combining technical means disclosed according tothe different embodiments are also included in the technical scope ofthe present invention. Furthermore, a configuration in which elementsdescribed in the respective embodiments and having mutually the sameeffects, are substituted for one another is also included.

INDUSTRIAL APPLICABILITY

An aspect of the present invention can be utilized, for example, in acommunication system, communication equipment (for example, a cellularphone apparatus, a base station apparatus, a wireless LAN apparatus, ora sensor device), an integrated circuit (for example, a communicationchip), or a program.

REFERENCE SIGNS LIST

-   1 (1A, 1B, 1C) Terminal apparatus-   3 Base station apparatus-   10, 30 Radio transmission and/or reception unit-   11, 31 Antenna unit-   12, 32 RF unit-   13, 33 Baseband unit-   14, 34 Higher layer processing unit-   15, 35 Medium access control layer processing unit-   16, 36 Radio resource control layer processing unit

The invention claimed is:
 1. A terminal apparatus comprising: receptioncircuitry configured to detect a Downlink Control Information (DCI)format; and transmission circuitry configured to transmit HybridAutomatic Repeat request ACKnowledgement (HARQ-ACK) informationgenerated based on one or more Physical Downlink Shared Channels(PDSCHs) associated with a PDSCH Group Indicator, wherein in a case thatthe DCI format includes a PDSCH Group Indicator field, a value of thePDSCH Group Indicator is indicated based on the PDSCH Group Indicatorfield, in a case that the DCI format does not include a PDSCH GroupIndicator field, the value of the PDSCH Group Indicator is prescribedvalue.
 2. A base station apparatus comprising: transmission circuitryconfigured to a Downlink Control Information (DCI) format; and receptioncircuitry configured to receive Hybrid Automatic Repeat requestACKnowledgement (HARQ-ACK) information generated based on one or morePhysical Downlink Shared Channels (PDSCHs) associated with a PDSCH GroupIndicator, wherein in a case that the DCI format includes a PDSCH GroupIndicator field, a value of the PDSCH Group Indicator is indicated basedon the PDSCH Group Indicator field, in a case that the DCI format doesnot include a PDSCH Group Indicator field, the value of the PDSCH GroupIndicator is prescribed value.
 3. A communication method used for aterminal apparatus, the communication method comprising: detecting aDownlink Control Information (DCI) format; and transmitting HybridAutomatic Repeat request ACKnowledgement (HARQ-ACK) informationassociated with one or more Physical Downlink Shared Channels (PDSCHs)associated with a PDSCH Group Indicator, wherein in a case that the DCIformat includes a PDSCH Group Indicator field, a value of the PDSCHGroup Indicator is indicated based on the PDSCH Group Indicator field,in a case that the DCI format does not include a PDSCH Group Indicatorfield, the value of the PDSCH Group Indicator is prescribed value.